HK1061839A

HK1061839A - Process for producing 5-nitro-3, 4-dihydro- 1(2h)-naphthalinone, 1, 5-naphthalenediamine and 1, 5-naphthalene disocyanate

Info

Publication number: HK1061839A
Application number: HK04104823.1A
Authority: HK
Inventors: Zechlin Joachim; Verkerk Kai; Wastian Dietmar; Joschek Katrin; Loddenkemper Tim; Pinke Wilfried; Schelhaas Michael; Ronge Georg
Original assignee: Bayer Aktiengesellschaft
Priority date: 2002-06-03
Filing date: 2004-07-05
Publication date: 2004-10-08

Description

Process for preparing 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone, 1, 5-naphthalenediamine and 1, 5-naphthalene diisocyanate

Technical Field

The invention relates to a method for producing 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone (naphthyridone) by hydrolyzing 4- (2-nitrophenyl) n-butyronitrile and reacting the 4- (2-nitrophenyl) n-butyric acid formed therefrom.

Background

5-Nitro-3, 4-dihydro-1 (2H) -naphthalenone is an intermediate for the preparation of 1, 5-naphthalenediamine, 1, 5-naphthalenediamine being prepared from 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone by sequential amination, aromatization and hydrogenation. The 1, 5-naphthalenediamine may be further reacted with phosgene to produce 1, 5-naphthalene diisocyanate.

Various methods for preparing 1, 5-naphthalenediamines are known from the literature. The preparation of 1, 5-naphthalenediamines is generally started with appropriately substituted naphthalenes. Thus, JP-A2-07278066 describes a method for synthesizing 1, 5-naphthalenediamine via amine-bromine exchange in 1, 5-bromoaminonaphthalene. In this process, the desired educt is prepared by bromination of 1-nitronaphthalene.

JP-A2-04154745, JP-A2-56059738 and DE-A1-2523351 describe processes for the synthesis of 1, 5-naphthalenediamine and 1, 8-naphthalenediamine by reducing a mixture of 1, 5-dinitronaphthalene and 1, 8-dinitronaphthalene. DE-C1-3840618 describes the synthesis of 1, 5-naphthalenediamines by alkaline hydrolysis of disodium naphthalene-1, 5-disulfonate and subsequent reaction with ammonia.

All of the above methods have the following disadvantages: i.e. the product or intermediate product formed during the process is obtained in the form of an isomeric mixture which, in addition to the 1, 5-isomer, contains the other isomer which has to be separated off. Furthermore, in particular, the process described in DE-C1-3840618 is carried out under very vigorous and corrosive reaction conditions.

Summary of The Invention

Thus, the present invention provides a simple process for preparing intermediates for the production of 1, 5-naphthalenediamine, whereby 1, 5-naphthalenediamine can be prepared without forming a large amount of other isomers which must be separated. The invention also provides processes for preparing 1, 5-naphthalenediamine and 1, 5-naphthalene diisocyanate based on these intermediates.

Detailed Description

It has now been found that 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone, which is useful as an intermediate for the preparation of 1, 5-naphthalenediamine, can be easily prepared in a highly isomerically pure form from 4- (2-nitrophenyl) n-butyronitrile.

The invention relates to a method for producing 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone, comprising converting 4- (2-nitrophenyl) n-butyronitrile into 4- (2-nitrophenyl) n-butyric acid.

4- (2-nitrophenyl) n-butyronitrile may be produced from o-nitrotoluene and acrylonitrile, the reaction preferably being carried out at a temperature of-10 ℃ to 100 ℃. The reaction is more preferably carried out at a temperature of from 20 ℃ to 75 ℃, most preferably from 30 ℃ to 60 ℃.

The reaction is carried out using base catalysis. Oxides, hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium or aluminum can be used as the base. Sodium hydroxide and potassium hydroxide are particularly preferred. Preferably, a solution of a base is used. It is also possible to use a solution of a base in combination with a phase transfer catalyst. An example of such a phase transfer catalyst is a quaternary ammonium salt. Suitable ammonium compounds include, but are not limited to, tetraalkylammonium halides and tetraalkylammonium hydrogen sulfates, such as tributylmethylammonium chloride, trioctylammonium chloride, tetrabutylammonium chloride or tetrabutylammonium hydrogen sulfate. It is also suitable to use the corresponding tetraalkyl or tetraarylphosphonium salts such as tetramethylphosphonium bromide and tetraphenylphosphonium bromide, and also to use cosolvents such as polyethylene glycol dimethyl ether.

It is preferred to use an alkaline solution without a phase transfer catalyst.

In principle, water and all alkali-resistant organic solvents are suitable as solvents. Solvents which are preferably used are aromatic solvents such as benzene, toluene, xylene, -chlorobenzene, dichlorobenzene, trichlorobenzene, nitrobenzene or nitrotoluene, and also dimethyl sulfoxide, dimethylformamide and aliphatic hydrocarbons such as solvent light oil (ligroin), cyclohexane, pentane, hexane, heptane, octane. Dimethyl sulfoxide is preferably used in a concentration of 10 to 80 wt.%, more preferably in a concentration of 30 to 60 wt.%, wherein the weight percentages are based on o-nitrotoluene.

The ortho-nitrotoluene is preferably used in excess. It is preferable to use 1 to 40 moles of o-nitrotoluene, more preferably 5 to 20 moles of o-nitrotoluene per mole of acrylonitrile.

In one embodiment of the present invention, the process for preparing 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone comprises the steps of: a) reacting 4- (2-nitrophenyl) n-butyronitrile with an acid or a base to produce 4- (2-nitrophenyl) n-butyl

Butyric acid, and b) cyclisation of the 4- (2-nitrophenyl) n-butyric acid formed in step a) to give 5-nitro-

3, 4-dihydro-1 (2H) -naphthalenone.

The hydrolysis of 4- (2-nitrophenyl) n-butyronitrile to 4- (2-nitrophenyl) n-butyric acid is carried out without solvent or in a solvent, in the presence of one or more acids or one or more bases.

Suitable acids include, but are not limited to, strong acids such as dilute or concentrated mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and hydrogen and dihydrogen sulfates.

Suitable bases include, but are not limited to, strong bases such as oxides, hydroxides, and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, or aluminum and mixtures thereof, and aqueous solutions or suspensions of hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, or aluminum. Aqueous solutions of sodium hydroxide or potassium hydroxide are particularly suitable.

Suitable solvents include, but are not limited to, straight, branched or cyclic aliphatic hydrocarbons such as solvent light oil or cyclohexane, pentane, hexane, heptane, octane, and aromatic solvents such as benzene, toluene, xylene, monochlorobenzene, dichlorobenzene, trichlorobenzene. The process is preferably carried out in the absence of a solvent.

Preferably, 0.5 to 20 moles, more preferably 1 to 10 moles, most preferably 1.5 to 6 moles of the acid or base are used per mole of 4- (2-nitrophenyl) n-butyronitrile.

The reaction is preferably carried out at a temperature of from 0 ℃ to 150 ℃, more preferably from 30 ℃ to 120 ℃, most preferably from 50 ℃ to 100 ℃.

The synthesis of 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone from the ring of 4- (2-nitrophenyl) n-butyric acid is carried out without or in a solvent in the presence of one or more acids. Suitable acids include, but are not limited to, strong lewis acids or bronsted acids, such as aluminum trichloride, boron trifluoride, sulfuric acid, phosphoric acid, polyphosphoric acid, phosphorus pentoxide, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, niobic acid, or mixtures of antimony pentafluoride and fluorosulfuric acid. Mixtures of acids may also be used. It is also possible to use heterogeneous acids (hetereogenized acids), such as polyphosphoric acid or partially fluorinated or perfluorinated aryl or alkylsulfonic acids, or partially fluorinated or perfluorinated polyaryl or alkylsulfonic acids, on a carrier such as silica, alumina.

Preferably, from 0.1 to 100 moles of acid, more preferably from 0.5 to 50 moles of acid, most preferably from 1 to 25 moles of acid are used per mole of 4- (2-nitrophenyl) n-butyric acid.

The reaction is preferably carried out at a temperature of from 50 ℃ to 300 ℃, more preferably from 100 ℃ to 250 ℃, most preferably from 120 ℃ to 230 ℃.

Suitable solvents include, but are not limited to, linear, branched or cyclic aliphatic hydrocarbons such as naphtha or cyclohexane, pentane, hexane, heptane, octane, aromatic solvents such as benzene, toluene, xylene, monochlorobenzene, dichlorobenzene, trichlorobenzene, solvents such as dimethyl sulfoxide, dimethylformamide, and high boiling point alkylbenzene derivatives or benzene derivatives stable at high temperatures such as isomeric dibenzyltoluenes, di-and triarylalkyl, di-or triaryloxide, terphenyl and its partially hydrogenated and hydrogenated analogs, alkylated or non-alkyl substituted benzyltoluenes. Solvent-free processes are also possible.

All reaction steps can be carried out continuously or batchwise, for example in stirred tank reactors or in tubular reactors.

In another embodiment of the present invention, the process for preparing 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone comprises the steps of: a) reacting 4- (2-nitrophenyl) n-butyronitrile with an acid or a base to produce 4- (2-nitrophenyl) n-butyl

Butyric acid, b) chlorination of the 4- (2-nitrophenyl) n-butyric acid formed in step a) to form 4- (2-nitro-acid

Phenylphenyl) n-butyryl chloride, and c) cyclizing the 4- (2-nitrophenyl) n-butyryl chloride formed in step b) to form 5-nitro

-3, 4-dihydro-1 (2H) -naphthalenone.

In analogy to step a) of the first embodiment, the reaction (hydrolysis) of 4- (2-nitrophenyl) n-butyronitrile with an acid or a base to give 4- (2-nitrophenyl) n-butyric acid is carried out without solvent or in a solvent in the presence of one or more acids or one or more bases.

The chlorination of 4- (2-nitrophenyl) n-butyric acid to produce 4- (2-nitrophenyl) n-butyric acid chloride is carried out with a chlorinating agent such as chlorine, thionyl chloride, phosgene, phosphorus oxychloride, phosphorus trichloride or phosphorus pentachloride. Preference is given to using thionyl chloride or phosgene.

Suitable solvents include, but are not limited to, straight, branched or cyclic aliphatic hydrocarbons such as solvent light oil or cyclohexane, pentane, hexane, heptane, octane, and aromatic solvents such as benzene, xylene, monochlorobenzene, dichlorobenzene, trichlorobenzene. The process is preferably carried out in the absence of a solvent.

The reaction is preferably carried out at a temperature of from 0 ℃ to 250 ℃, more preferably from 20 ℃ to 200 ℃, most preferably from 30 ℃ to 180 ℃.

The cyclization of the 4- (2-nitrophenyl) n-butyryl chloride formed in step b) to 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone is carried out without solvent or in a solvent in the presence of an acid. Suitable acids include, but are not limited to, strong lewis acids or bronsted acids such as aluminum trichloride, ferric trichloride, tin dichloride, titanium tetrachloride, boron trifluoride, sulfuric acid, phosphoric acid, polyphosphoric acid, phosphorus pentoxide, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, niobic acid, or mixtures of antimony pentafluoride and fluorosulfuric acid. Mixtures of acids may also be used. It is also possible to use heterogeneous acids such as polyphosphoric acid or partially fluorinated or perfluorinated aryl or alkylsulfonic acids or partially fluorinated or perfluorinated polyaryl or alkylsulfonic acids on a support such as silica, alumina.

Suitable solvents include, but are not limited to, linear, branched or cyclic aliphatic hydrocarbons such as solvent light oil or cyclohexane, pentane, hexane, heptane, octane, aromatic solvents such as monochlorobenzene, dichlorobenzene, trichlorobenzene, solvents such as dimethyl sulfoxide, dimethylformamide, and high boiling point alkylbenzene derivatives or benzene derivatives that are stable at high temperatures such as the isomeric dibenzyltoluenes, di-and triarylalkyl, di-or triaryl oxides, terphenyls and their partially hydrogenated and hydrogenated analogs, alkylated or non-alkyl substituted benzyltoluenes. Solvent-free processes are also possible.

Preferably, from 0.1 to 100 moles of acid, more preferably from 0.5 to 50 moles of acid, and most preferably from 1 to 25 moles of acid are used per mole of 4- (2-nitrophenyl) n-butyryl chloride.

The invention also relates to a process for preparing 1, 5-naphthalenediamine, which comprises converting 4- (2-nitrophenyl) n-butyronitrile to 4- (2-nitrophenyl) n-butyric acid.

1, 5-naphthalenediamine is prepared from 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone by amination, aromatization and hydrogenation.

Amination of 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone to a nitroimine or nitroenamine is carried out by reaction with ammonia, preferably in the presence of an ammonium salt such as ammonium chloride.

The aromatization or dehydrogenation of nitroaniline 5-nitro-3, 4-dihydro-1-naphthylamine or nitroimine 5-nitro-3, 4-dihydro-1 (2H) -naphthylimine to form 5-nitro-1-naphthylamine or 5-nitroso-1-naphthylamine or a mixture of the two compounds is carried out, for example, in an inert solvent, without the use of a catalyst or in the presence of a catalyst. In addition to the dehydrogenation product 5-nitro-1-naphthylamine, 5-nitroso-1-naphthylamine is formally formed in proportion. Traces of 1, 5-naphthalenediamine were also formed. The product can be further processed in any mixing ratio.

Suitable solvents include, but are not limited to, ammonia and straight, branched or cyclic aliphatic hydrocarbons such as solvent light oil or cyclohexane, as well as acetonitrile, dimethylformamide, dimethylacetamide, and aromatic solvents such as benzene, toluene, xylene, nitrobenzene, nitrotoluene or monochlorobenzene, dichlorobenzene, trichlorobenzene. Aromatization can also be carried out without a solvent.

Suitable catalysts include, but are not limited to, the dehydrogenation catalysts described in the literature (section 1 of the chapter R * mppLexikon Chemie, Georg Thieme Verlag, Stuttgart, 10th Edition1997, p.891, "dehydrogenation"; Ullmann's Encyclopedia of Industrial Chemistry, VCH Verlagsgesellschaft mbH, Weinheim, 5th Edition 1989, Vol A13, "hydrogenation and dehydrogenation"; Subchapter 2 "dehydrogenation", p.494-497). These catalysts include metals of groups 8 to 10 of the periodic Table (G.J.Leigh [ Editor ], Nomenclature of organic Chemistry, Recommendations 1990, Blackwell Scientific Publications, Oxford, Chapter I3.8.1 "elements of the periodic Table and their subdivisions", p.41-43), in particular platinum, palladium, ruthenium and iridium, iron, cobalt, nickel and combinations thereof. These metals may also be used with other metals such as lanthanum, scandium, vanadium, chromium, molybdenum, tungsten, manganese, tin, zinc, copper, silver or indium. The above metals may be present as pure elements, oxides, sulfides, halides, carbides or nitrides, or may be used in combination with organic ligands. Hydrocarbon compounds having electron donating groups such as amines, nitriles, phosphines, thiols, thioethers, alcohols, ethers or carboxylic acids are suitable ligands. The catalyst may optionally be applied to a support. Suitable supports are activated carbon, alumina, silica, zirconia, zinc oxide, zeolites.

The process may optionally be carried out in the presence of an oxidant such as oxygen or air. The reaction is preferably carried out at a temperature of 50 ℃ to 250 ℃, more preferably 100 ℃ to 200 ℃.

The subsequent hydrogenation of 5-nitro-1-naphthylamine or 5-nitroso-1-naphthylamine or a mixture of the two compounds to form 1, 5-naphthalenediamine is carried out in the presence of a hydrogenation catalyst.

Suitable hydrogenation catalysts include all heterogeneous catalysts known as hydrogenation catalysts (R * mpp Lexikon Chemie, Georg Thieme Verlag, Stuttgart, 10th Edition1997, p.1831, Chapter "hydrogenation"; Ullmann's Encyclopedia of Industrial Chemistry, VCH Verlagsgesellschaft mbH, Weinheim, 5th Edition 1989, Vol A13, Chapter "hydrogenation and dehydrogenation", Subchapter 1.2 "catalyst", p.488). Preferred catalysts are metals of groups 8 to 10 of the periodic table (g.j. leigh [ Editor ], Nomenclature of organic Chemistry, recommerdations 1990, Blackwell Scientific publications, Oxford, Chapter I-3.8.1 "groups of the periodic table and their subdivisions", p.41-43), the metal content preferably being from 0.01 wt.% to 50 wt.%, more preferably from 0.1 wt.% to 20 wt.%, based on the total weight of the catalyst, of copper or chromium on a suitable support. Catalysts containing one or more of the above metals may also be used. Preferred metals are in particular platinum, palladium and rhodium; platinum and palladium are particularly preferred. Other preferred catalysts are Raney nickel and supported nickel catalysts. The metals or their compounds mentioned above can also be used in pure form as solid substances. Examples of metals in pure form are palladium black and platinum black.

In a variant of the batch process, the catalyst may preferably be used in an amount of 0.01 wt.% to 50 wt.%, more preferably 0.01 wt.% to 20 wt.%, most preferably 0.01 wt.% to 10 wt.%, wherein the weight percentages are based on 5-nitro-1-naphthylamine or 5-nitroso-1-naphthylamine. When the reaction is carried out continuously, for example in a stirred tank reactor using a pulverulent catalyst or in the trickle phase on a fixed-bed catalyst, a loading ratio of from 0.01g to 500g, preferably from 0.1g to 200g, more preferably from 1g to 100g of 5-nitro-1-naphthylamine or 5-nitroso-1-naphthylamine per g of catalyst per hour can be established.

The reaction temperature is preferably-20-150 ℃, and more preferably 40-120 ℃; the hydrogen pressure is preferably from 0.1 to 150 bar, more preferably from 0.5 to 70 bar, most preferably from 1 to 50 bar.

Preferably, the same catalyst is used for aromatization (dehydrogenation) and subsequent hydrogenation, and these two steps can be carried out sequentially in one reaction vessel.

For hydrogenation, suitable solvents include, but are not limited to, straight or branched chain aliphatic alcohols such as methanol, ethanol, propanol, butanol, straight, branched or cyclic aliphatic hydrocarbons such as solvent light oil or cyclohexane, and dimethylformamide, dioxane, dimethylacetamide, and aromatic solvents such as benzene, toluene, xylene, nitrobenzene, nitrotoluene or monochlorobenzene, dichlorobenzene, trichlorobenzene.

The 1, 5-naphthalenediamine obtained by the process of the present invention may be treated with phosgene according to a known method to obtain 1, 5-naphthalenediisocyanate.

The invention is further illustrated, but is not intended to be limited, by the following examples in which all parts and percentages are by weight unless otherwise specified.

Examples Example 1: preparation of 4- (2-Nitro) Nitro by hydrolysis of 4- (2-Nitrophenyl) n-Butonitrile with phosphoric acid

Phenyl) n-butyric acid

190g of 4- (2-nitrophenyl) n-butyronitrile (1mol) were placed with 1153g of phosphoric acid (85 wt.%) (10mol) in a 2L four-necked stirred flask equipped with a paddle stirrer, a thermometer and a condenser. The reaction mixture was heated to 100 ℃ with stirring and stirred at 100 ℃ for 17 hours. The reaction mixture was slowly cooled to room temperature with stirring, during which the emulsified 4- (2-nitrophenyl) n-butyric acid solidified. Excess phosphoric acid was decanted and the solid material was dissolved in 1000ml chloroform. The solution was transferred to a separating funnel, washed 3 times with 50ml of distilled water each time to remove the phosphoric acid and evaporated to a small volume in a rotary evaporator at 80 ℃ and 20 mbar. The residue (4- (2-nitrophenyl) n-butyric acid) was broken up and dried in a desiccator with phosphorus pentoxide to constant weight.

The decanted phosphoric acid was diluted with 2L of distilled water and extracted with 500ml of chloroform. The chloroform extracts were evaporated to a small volume at 80 ℃ and 20 mbar on a rotary evaporator and the residue (4- (2-nitrophenyl) n-butyric acid) was combined with the residue obtained after drying described above.

Final weight of 4- (2-nitrophenyl) n-butyric acid: 200.2g, corresponding to a crude yield of 95.8% (purity: 99.3%, determined by Gas Chromatography (GC)).Example 2: preparation of 5-Nitro-substituted derivatives by cyclization of 4- (2-nitrophenyl) -n-butyric acid with phosphoric acid

3, 4-dihydro-1 (2H) -naphthalenones

50g of dibenzyltoluene (isomer mixture, trade name MARLOTHERM SH, Sasol Germany GmbH) and 10g of polyphosphoric acid (85 wt.% P)₄O₁₀) Placed in a two-necked flask equipped with a magnetic stirrer, distillation head, vacuum receiver, receiving flask and heatable addition funnel. An addition funnel heated to 90 ℃ was charged with a solution of 2g of 4- (2-nitrophenyl) n-butyric acid (NPBS, 9.57mmol) in 20g of dibenzyltoluene (mixture of isomers, under the trade name MARLOTHERM SH, Sasol Germany GmbH). The apparatus was evacuated and heated to reflux temperature (163 ℃, 0.2 mbar) with stirring. The solution was continuously added dropwise over 20 minutes. The amount of distillate distilled out was adjusted to be equal to the amount of feed so that the reaction volume at the bottom of the flask was kept constant. When all solutions have been added, the mixture is washed again with 20g of dibenzyltoluene (isomer mixture, trade name MARLOTHERM SH, Sasol Germany GmbH) and purified by distillation.

The distillate contained 626mg of 5-nitro-3, 4-dihydro-1 (2H) -Naphthalenone (NT) and 1268mg of NPBS (determined by GC/internal standard method): NT yield: conversion of 34.2% NPBS: 36.8% selectivity: 93.1 percentExample 3: prepared by cyclization of 4- (2-nitrophenyl) -n-butyric acid with trifluoromethanesulfonic acid

5-nitro-3, 4-dihydro-1 (2H) -naphthalenones

1g of 4- (2-nitrophenyl) -n-butyric acid (NPBS, 4.78mmol) and 18g of trifluoromethanesulfonic acid (TFMA) (119.9mmol) are placed in a 100ml two-necked flask equipped with a reflux condenser and a magnetic stirrer at 20 ℃. The solution was heated with stirring in an oil bath preheated to 130 ℃ and then stirred at 130 ℃ for 45 minutes. The solution was cooled and transferred to a micro-distillation apparatus. Overhead distillation at 52 deg.CExcess TFMA was distilled off at temperature and pressure of 0.5 mbar. The bottom of the column contained 0.914g of 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone and 3.44g of TFMA (determined by GC-ISTD/internal standard): NT yield: conversion of 99.3% NPBS: 100% selectivity: 99.3 percent ofExample 4: preparation by chlorination of 4- (2-nitrophenyl) -n-butyric acid using thionyl chloride

4- (2-Nitrophenyl) -n-butyryl chloride

744.3g of 4- (2-nitrophenyl) -n-butyric acid (NPBA, 3.56mol) were placed in a four-necked stirred flask equipped with a paddle stirrer, a thermometer, a condenser and a drying lance (drying pillow). 635.5g of thionyl chloride (5.34mol) were added dropwise at room temperature with stirring. During the dropwise addition, the temperature was lowered to-6 ℃. The reaction mixture was slowly heated to reflux temperature (up to 80 ℃) by mushroom heater. During this heating, a reddish-brown slightly viscous liquid is formed, with vigorous evolution of gas. The reaction mixture was stirred under reflux for 1 hour. The excess thionyl chloride was distilled off under water jet vacuum at 80 ℃. The acid chloride obtained was purified by flash distillation in a hot gas distillation unit (260 ℃ hot gas, column bottom temperature < 180 ℃ C., pressure < 1 mbar).

And (3) distillate: 767.7g of 4- (2-nitrophenyl) -n-butyryl chloride correspond to a crude yield of 94.8% (purity: 92.7%, determined by GC).Example 5: preparation of 4- (2-Nitro) Nitro by Chlorination of 4- (2-Nitrophenyl) -n-Butanoic acid with phosgene

Phenyl) -n-butyryl chloride

In a 250ml four-necked flask equipped with a stirrer, a thermometer and a condenser (connected to a phosgene destruction column), 20g of 4- (2-nitrophenyl) -n-butyric acid (95.7mmol) were dissolved in 180g of 1, 2, 4-trichlorobenzene at 35 ℃. Phosgene was introduced at a rate of 100 g/hour through a submerged glass tube. The reaction mixture was heated to 180 ℃ over 20 minutes and chlorinated with phosgene at a rate of 100 g/h for 2 hours with constant stirring. The dark orange-brown solution was degassed by stripping with nitrogen at 100 ℃.1, 2, 4-trichlorobenzene is distilled off in a hot gas distillation apparatus (140 ℃ C. hot gas, pressure < 1 mbar).

Residue: 21.3g of 4- (2-nitrophenyl) -n-butyryl chloride, corresponding to a crude yield of 97.7% (purity: 91.0%, determined by GC).Example 6: prepared by cyclizing 4- (2-nitrophenyl) -n-butyryl chloride with aluminum trichloride

5-nitro-3, 4-dihydro-1 (2H) -naphthalenones

762.2g of 4- (2-nitrophenyl) -n-butyryl chloride (from example 4) were dissolved in 4.5L of carbon disulfide in a 10L four-necked stirred flask equipped with a paddle stirrer, thermometer, condenser, drying spray gun and powder addition funnel. 535.8g of aluminum chloride (4.0mol) were added via a powder addition funnel at 15 ℃. During this addition, the aluminum chloride was almost completely dissolved in the solution and the temperature at the bottom of the column was raised to 30 ℃. Two phases are formed in a short time; the following ketone-aluminum chloride complex phase was reddish-brown and was an oil. When the addition of aluminum chloride was complete, stirring was continued at room temperature for 4 hours during which time the oil phase was completely solidified. The carbon disulfide was decanted and 2.6L of distilled water was added to the solid phase under cooling to decompose the ketone-aluminum chloride complex. The hydrolysis was accelerated by the addition of 2.6L of dichloromethane and the 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone formed was completely dissolved. The organic phase was washed 3 times with a total of 1.4L of distilled water, 1 time with 1000mL of sodium hydroxide solution (1 wt.% NaOH), and then washed with distilled water to neutralize it. The solution was evaporated to a small volume in a rotary evaporator and the precipitated 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone was dried to constant weight with phosphorus pentoxide in a desiccator.

Final weight: 548.5g of 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone corresponds to a crude yield of 85.7% (purity: 99.5%, determined by GC).Example 7: preparation of 5-Nitro-nitryl by cyclization of 4- (2-nitrophenyl) -n-butyryl chloride with phosphoric acid

3, 4-dihydro-1 (2H) -naphthalenones

50g of dibenzyltoluene (isomer mixture, trade name MARLOTHERM SH, Sasol Germany GmbH) and 10g of polyphosphoric acid (85 wt.% P)₄O₁₀) Placed in a two-necked flask equipped with a magnetic stirrer, distillation head, vacuum receiver, receiving flask and heatable addition funnel. The addition funnel heated to 90 ℃ was charged with a solution of 2.2g of 4- (2-nitrophenyl) n-butyryl chloride (NPBS, 9.67mmol) in 20g of dibenzyltoluene (mixture of isomers, trade name MARLOTHERM SH, Sasol Germany GmbH). The apparatus was evacuated and heated to reflux temperature (166 ℃, 0.1 mbar) with stirring. The NPBC solution was then added dropwise continuously over 20 minutes to a previously prepared solution of phosphoric acid and dibenzyltoluene (isomer mixture, under the trade name MARLOTHERM SH, Sasol Germany GmbH). Immediately after the start of the dropwise addition of the acid chloride solution, the pressure in the apparatus was raised to about 2 mbar due to the formation of hydrogen chloride gas. The amount of distillate distilled out was adjusted to be equal to the amount of feed so that the reaction volume at the bottom of the flask was kept constant. When all solutions have been added, the mixture is washed again with 20g of dibenzyltoluene (isomer mixture, trade name MARLOTHERM SH, Sasol Germany GmbH) and purified by distillation.

The distillate contained 783g of 5-nitro-3, 4-dihydro-1 (2H) -Naphthalenone (NT) and 642g of NPBS (determined by GC/internal standard): NT yield: conversion of 42.7% NPBSC: 71.0% selectivity: 62.8 percent

Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims.

Claims

1. A process for preparing 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone comprising the steps of:

reacting 4- (2-nitrophenyl) -n-butyronitrile with an acid or a base to produce 4- (2-nitrophenyl) n-butyric acid;

optionally chlorinating 4- (2-nitrophenyl) n-butyric acid to produce 4- (2-nitrophenyl) n-butyric acid chloride; and

cyclization of 4- (2-nitrophenyl) n-butyric acid or 4- (2-nitrophenyl) n-butyryl chloride to give 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone.

2. The process of claim 1 wherein the acid in the reacting step is selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid, hydrogen sulfate and dihydrogen phosphate.

3. The process of claim 1 wherein the base in the reacting step is selected from the group consisting of oxides, hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium or aluminum and mixtures thereof, and aqueous solutions or suspensions of hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium or aluminum.

4. The method of claim 1, wherein said ring closure step is carried out in the presence of at least one agent selected from the group consisting of: aluminum trichloride, boron trifluoride, sulfuric acid, phosphoric acid, polyphosphoric acid, phosphorus pentoxide, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, niobic acid, and a mixture of antimony pentafluoride and fluorosulfuric acid.

5. The process of claim 1 wherein the optional chlorination step is carried out in the presence of at least one chlorinating agent selected from the group consisting of: chlorine, thionyl chloride, phosgene, phosphorus oxychloride, phosphorus trichloride, and phosphorus pentachloride.

6. The process of claim 1, wherein the 4- (2-nitrophenyl) n-butyronitrile is prepared by reacting o-nitrotoluene with acrylonitrile in the presence of a base.

7. A process for preparing 1, 5-naphthalenediamine, comprising the steps of:

reacting 4- (2-nitrophenyl) n-butyronitrile with an acid or a base to produce 4- (2-nitrophenyl) n-butyric acid;

optionally chlorinating 4- (2-nitrophenyl) n-butyric acid to produce 4- (2-nitrophenyl) n-butyric acid chloride;

cyclizing 4- (2-nitrophenyl) n-butyric acid or 4- (2-nitrophenyl) n-butyryl chloride to produce 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone;

aminating 5-nitro-3, 4-dihydro-1 (2H) -naphthalenone to produce 5-nitro-3, 4-dihydro-1 (2H) -naphthylamine or tautomeric 5-nitro-3, 4-dihydro-1 (2H) -naphthylimine;

aromatizing 5-nitro-3, 4-dihydro-1 (2H) -naphthylamine or the tautomeric 5-nitro-3, 4-dihydro-1 (2H) -naphthylimine to form 5-nitro-1-naphthylamine and/or 5-nitroso-1-naphthylamine; and

the 5-nitro-1-naphthylamine and/or 5-nitroso-1-naphthylamine are hydrogenated to form 1, 5-naphthalenediamine.

8. The process of claim 7 wherein the acid in the reacting step is selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid, hydrogen sulfate and dihydrogen phosphate.

9. The process of claim 7 wherein the base in the reacting step is selected from the group consisting of oxides, hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium or aluminum and mixtures thereof, and aqueous solutions or suspensions of hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium or aluminum.

10. The method of claim 7, wherein said ring closure step is carried out in the presence of at least one agent selected from the group consisting of: aluminum trichloride, boron trifluoride, sulfuric acid, phosphoric acid, polyphosphoric acid, phosphorus pentoxide, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, niobic acid, and a mixture of antimony pentafluoride and fluorosulfuric acid.

11. The process of claim 7 wherein the optional chlorination step is carried out in the presence of at least one chlorinating agent selected from the group consisting of: chlorine, thionyl chloride, phosgene, phosphorus oxychloride, phosphorus trichloride, and phosphorus pentachloride.

12. The process of claim 7 wherein said amination step is carried out by reaction with ammonia, optionally in the presence of an ammonium salt.

13. The process of claim 7, wherein the 4- (2-nitrophenyl) n-butyronitrile is prepared by reacting o-nitrotoluene with acrylonitrile in the presence of a base.

14. A process for preparing 1, 5-naphthalene diisocyanate, said process comprising the steps of:

aromatizing 5-nitro-3, 4-dihydro-1 (2H) -naphthylamine or the tautomeric 5-nitro-3, 4-dihydro-1 (2H) -naphthylimine to form 5-nitro-1-naphthylamine and/or 5-nitroso-1-naphthylamine;

hydrogenating 5-nitro-1-naphthylamine and/or 5-nitroso-1-naphthylamine to produce 1, 5-naphthalenediamine; and

reacting 1, 5-naphthalene diamine with phosgene to produce 1, 5-naphthalene diisocyanate.

15. The process of claim 14 wherein the acid in the reacting step is selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid, hydrogen sulfate and dihydrogen phosphate.

16. The process of claim 14 wherein the base in the reacting step is selected from the group consisting of oxides, hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium or aluminum and mixtures thereof, and aqueous solutions or suspensions of hydroxides and carbonates of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium or aluminum.

17. The method of claim 14, wherein said ring closure step is carried out in the presence of at least one agent selected from the group consisting of: aluminum trichloride, boron trifluoride, sulfuric acid, phosphoric acid, polyphosphoric acid, phosphorus pentoxide, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, niobic acid, and a mixture of antimony pentafluoride and fluorosulfuric acid.

18. The process of claim 14 wherein the optional chlorination step is carried out in the presence of at least one chlorinating agent selected from the group consisting of: chlorine, thionyl chloride, phosgene, phosphorus oxychloride, phosphorus trichloride, and phosphorus pentachloride.

19. The process of claim 14 wherein said amination step is carried out by reaction with ammonia, optionally in the presence of an ammonium salt.

20. The process of claim 14, wherein the 4- (2-nitrophenyl) n-butyronitrile is prepared by reacting o-nitrotoluene with acrylonitrile in the presence of a base.