Background:Recently, we developed a rapid procedure for the Leukart reaction and successfully applied it for the synthesis of substituted N-benzyl-N-methylformamides. Interestingly, in the reaction conducted on 4-isopropylbenzaldehyde, a large amount of a by-product, N,N-di-(4-isopropylbenzyl)-N-methylamine was produced with an isolated yield of 44.0%. N-(4-isopropylbenzyl)-N-methylformamide was produced with an isolated yield of 42.0%. The ratio of the yield of the dibenzyl product to the yield of the monobenzyl product was 1.04:1. Hypothesis:Based on the slightly higher electron-donating properties of the ethyl group, the reaction with N-ethylformamide may produce a higher yield of the respective dibenzyl product and a lower yield of the respective monobenzyl product compared to the reaction with N-methylformamide. Methods:The reaction was conducted on 10 mmol scale at 189°C. Column chromatography was used for the isolation of the products. NMR-spectroscopy and elemental analysis were used to determine the structures of the products. Results: The reaction was completed in 10 minutes. The isolated yields of N-ethyl-N,N-di-(4-isopropylbenzyl)amine (47.2%) and N-ethyl-N-(4-isopropylbenzyl)formamide (39.5%) appeared to be 3.2% higher and 2.5% lower than the yields of the respective products in the reaction with N-methylformamide. The ratio of yield of the dibenzyl product to the yield of the monobenzyl product shifted to 1.19:1. Conclusions:The results of the reaction support the initial hypothesis. The reaction provides a new method for the synthesis of N-ethyl-N-(4-isopropylbenzyl)formamide and N-ethyl-N,N-di-(4-isopropylbenzyl)amine.Both products of the reaction are new compounds.

Rapid synthesis of N-ethyl-N-(4-isopropylbenzyl)formamide

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.