CN106008478A - 2-carboxybenzaldehyde methylal hydrazine hydrate schiff base and preparing method thereof - Google Patents

Abstract

The invention discloses an o-carboxybenzaldehyde hydrazine Schiff base and a preparation method thereof. Using the special reaction system (mixed solvent) of o-carboxybenzaldehyde and hydrazine hydrate, the tetracyclic Schiff base complex is obtained by solution method, which is the o-carboxybenzaldehyde hydrazine hydrate Schiff base, and its molecular formula is C ₁₆ N ₂ O ₃ H ₁₁ , the structural formula is: The present invention has the advantages of simple process, low cost, good repeatability, etc., and successfully synthesizes the Schiff base tetracyclic complex, which provides a certain basis for the synthesis of new Schiff base complexes.

Description

adjacent Carboxybenzaldehyde hydrazine hydrazine Schiff base and preparation method thereof

technical field

The invention belongs to the technical field of Schiff base preparation, in particular to a Schiff base C ₁₆ N ₂ O ₃ H ₁₁ and a preparation method thereof.

Background technique

In recent years, the types and numbers of Schiff bases and their complexes have been increasing day by day. Because of their diversity and special structural properties, researchers have become very interested in their development and research. Schiff bases usually refer to a class of compounds containing imino groups (-C=N-), which are often obtained by condensation reactions between carbonyl and amino groups. Due to the diversity and selectivity of the functional group structures attached to the substituents of carbonyl and amino groups Many Schiff base ligands with different symmetric and asymmetric structures and properties such as chain, ring, and tooth can be synthesized by changing the type of substituents, such as bis-Schiff bases, asymmetric iso-bis-His The function and structure of the synthesized Schiff base products also have the characteristics of diversity and selectivity, and are widely used in our daily life. The benzene rings in o-carboxybenzaldehyde are conjugated to each other in the molecule, which is an excellent chromogenic group. There are more coordination points in the carboxyl and aldehyde groups, which can react well with other compounds. The chemical activity of hydrazine hydrate It is also very high. This patent uses these two compounds to react to synthesize the Schiff base shown in the title.

Contents of the invention

The object of the present invention is to provide a Schiff base C ₁₆ N ₂ O ₃ H ₁₁ o-carboxybenzaldehyde hydrazine hydrate and a preparation method thereof.

Idea of the present invention: O-carboxybenzaldehyde and hydrazine hydrate special reaction system (mixed solvent), obtain o-carboxybenzaldehyde hydrazine hydrate Schiff base by solution method.

The structural formula of o-carboxybenzaldehyde hydrazine hydrate Schiff base C ₁₆ N ₂ O ₃ H ₁₁ of the present invention is:

.

The o-carboxybenzaldehyde hydrazine hydrate Schiff base C ₁₆ N ₂ O ₃ H ₁₁ belongs to the triclinic crystal system, the space group is P ī, and the nitrogen atom on the hydrazine hydrate and the aldehyde group and the carboxyl group on the o-carboxybenzaldehyde form a special Synthesized by ring shrinkage reaction. Because o-carboxybenzaldehyde itself has a ring, a new ring is formed in the synthesis reaction, which increases the conjugation effect of the obtained Schiff base molecule, increases the intermolecular force, and enhances the stability.

The preparation method of the above-mentioned o-carboxybenzaldehyde hydrazine hydrazine Schiff base C ₁₆ N ₂ O ₃ H ₁₁ is:

(1) Weigh 0.5-1 mmol of o-carboxybenzaldehyde and dissolve it in 5-10 ml of absolute ethanol to obtain an alcohol solution of o-carboxybenzaldehyde.

(2) Weigh 0.5 ~ 1 mmol of hydrazine hydrate and pour it into the alcoholic solution of o-carboxybenzaldehyde prepared in step (1) to obtain an alcoholic solution of o-carboxybenzaldehyde hydrazine hydrate, then magnetically stir at 70°C After 2 to 3 hours, a light yellow solution with precipitation is formed, filtered after cooling, and the filtrate is naturally volatilized and crystallized at room temperature, and a white blocky crystal is obtained after one week, which is o-Carboxybenzaldehyde hydrazine hydrazine Schiff base C ₁₆ N ₂ O ₃ H ₁₁ .

The invention has the advantages of simple process, low cost, good repeatability, etc., and successfully synthesizes a novel polycyclic Schiff base compound, providing a certain basis for synthesizing a novel Schiff base.

Description of drawings

Fig. 1 is a molecular structure diagram of o-carboxybenzaldehyde hydrazine hydrazine Schiff base C ₁₆ N ₂ O ₃ H ₁₁ of the present invention.

detailed description

Example:

(1) Weigh 1 mmol (0.150 g) of o-carboxybenzaldehyde and dissolve it in 10 milliliters of absolute ethanol to obtain an alcoholic solution of o-carboxybenzaldehyde.

(2) Weigh 1 mmole (0.049 mL) of hydrazine hydrate and pour it into the alcoholic solution of o-carboxybenzaldehyde prepared in step (1) to prepare the alcoholic solution of o-carboxybenzaldehyde hydrazine hydrate, then at 70°C Stir magnetically for 2 hours to form a light yellow solution with precipitation. After cooling, filter it. The filtrate is naturally volatilized and crystallized at room temperature. After one week, a white blocky crystal is obtained, which is o-carboxybenzaldehyde hydrazine Schiff base C ₁₆ N ₂ O ₃ H ₁₁ . Its structural formula is:

The analysis of the crystal structure shows that the Schiff base belongs to the triclinic crystal system and the space group is Pī. It is synthesized by the special ring condensation reaction between the nitrogen atom of hydrazine hydrate and the aldehyde group and carboxyl group of o-carboxybenzaldehyde. Because o-carboxybenzaldehyde itself has a ring, a new ring is formed in the synthesis reaction, which increases the conjugation effect of the obtained Schiff base molecule, increases the intermolecular force, and enhances the stability.

Claims (2)

1. a 2-carboxybenzaldehyde contracting hydrazine hydrate schiff bases, it is characterised in that the molecular formula of this 2-carboxybenzaldehyde contracting hydrazine hydrate schiff bases is C₁₆N₂O₃H₁₁, its structural formula is:

；

Described 2-carboxybenzaldehyde contracting hydrazine hydrate schiff bases belongs to anorthic system, and space group is P ī, nitrogen-atoms on hydrazine hydrate and aldehyde radical on 2-carboxybenzaldehyde and carboxyl special Norfloxacin Reaction synthesis occurs；There is ring in 2-carboxybenzaldehyde itself, synthetic reaction has again new ring to generate so that this schiff bases molecular conjugation effect increases, and intermolecular force increases, and stability strengthens.

2. the method preparing 2-carboxybenzaldehyde contracting hydrazine hydrate schiff bases as claimed in claim 1, its spy concretely comprises the following steps being:

(1) weigh 0.5 ~ 1 mM of 2-carboxybenzaldehyde to be dissolved in 5 ~ 10 milliliters of dehydrated alcohol, join to obtain the alcoholic solution of 2-carboxybenzaldehyde；

(2) weigh in the alcoholic solution that 0.5 ~ 1 mM of hydrazine hydrate pours the 2-carboxybenzaldehyde that step (1) is joined into, prepare the alcoholic solution of 2-carboxybenzaldehyde hydrazine hydrate, then magnetic agitation 2 ~ 3 hours at 70 DEG C, form the faint yellow solution with precipitation, cooled and filtered, filtrate is volatilized the most naturally crystallization, obtain the crystal of white chunks after one week, be 2-carboxybenzaldehyde contracting hydrazine hydrate schiff bases C₁₆N₂O₃H₁₁。