Unlock instant, AI-driven research and patent intelligence for your innovation.

Improved method for synthesizing amino formic acid ester compound

A technology of carbamate and oxime carbamate, which is applied in the field of preparing carbamate compounds, can solve undisclosed problems and achieve the effect of increasing the production rate

Inactive Publication Date: 2001-04-11
ROHM & HAAS CO
View PDF2 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This patent document does not disclose that certain catalysts are particularly effective in reducing the formation of by-products in the production of urethanes

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] This example illustrates the effectiveness of the catalyst of the present invention.

[0032] 1 g (4.9 mmol) of dibromoformaldoxime was charged in a 50 ml three-necked round-bottomed flask equipped with a stirring bar and a nitrogen atmosphere, and 10 g of dichloromethane containing 2% (by weight) of a suitable catalyst was added thereto. The mixture was stirred until the solids were all dissolved. Then 0.49 g (4.9 mmol) of n-butyl isocyanate was added to the flask. The reaction mixture was stirred at room temperature.

[0033] After 0.5 hours and 16 hours of reaction, a portion of the reaction mixture (50 mg) was taken out, and a portion of the mixture taken out was quenched with a 50 / 50 (v / v) hexane / ethyl acetate mixture, and then analyzed by GC to determine the formation of Percentage of N-n-butyldibromoformaldoxime carbamate and by-products. The identity of N-n-butyldibromoformaldoxime carbamate and by-products was determined by comparison with the compound's ana...

Embodiment 2

[0038] This example shows the range of catalysts used in the present invention.

[0039] Use the catalyst listed in Table 2 to repeat the process of Example 1 in indicated amounts. Sampling and analysis by the method of Example 1. The percent carbamate and by-products formed are reported in Table 2.

[0040] Table 2: Percent carbamate formation *NA=not analyzed

[0041] These data indicate that 0.5% by weight zinc acetylacetonate provides a purer carbamate in higher yield than other known catalysts.

Embodiment 3

[0043] This example illustrates some solvents suitable for use in the present invention.

[0044] Using the solvents listed in Table 3, the process of Example 1 was repeated with zinc acetylacetonate as the catalyst. After 0.5 hours and 16 hours of reaction, a reaction sample was taken out, and the sample was analyzed by GC for the amount of carbamate formed. The results are reported in Table 3.

[0045] Table 3: Percent carbamate formation *NA=not analyzed

[0046] These data indicate that some types of solvents are suitable for use in the process of the invention.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

Disclosed is a method for the preparation of carbamate compounds substantially free of by-products; the carbamate compounds being prepared by reacting an isocyanate with a hydroxylated compound in the presence of certain catalysts that increase the rate of carbamylation while decreasing the rate of by-product formation.

Description

Background of the invention [0001] The present invention relates to a method for preparing carbamate compounds. In particular, the present invention relates to the use of a class of catalysts which increase the rate of formation of carbamate compounds while substantially reducing the rate of by-product formation. [0002] Carbamate compounds are a very important class of organic compounds in industry. Carbamates are used as intermediates in the synthesis of many organic compounds such as microbicides, pesticides and pharmaceutical agents. Many carbamates are themselves familiar microbicides, pesticides and pharmaceutical agents. [0003] Urethane compounds can be synthesized by various methods including reaction of amides with appropriate catalysts in the presence of alcohols, alcohols with cyanogen halides, alkyl hypochlorites with isonitriles, haloformates with amines Reacts with isocyanates and oximes or alcohols. The most important processes for preparing urethane comp...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): B01J23/06B01J27/128B01J27/135B01J27/138B01J31/02B01J31/04B01J31/12C07B61/00C07C269/02C07C271/20C07C271/60C08G18/16
CPCC07C269/02C07C271/60C08G18/16
Inventor J·V·伯里尔
Owner ROHM & HAAS CO