Abstract

DEET (N, N Diethyl m-toluamide) and DEPA (Diethyl phenyl acetamide) are synthetic compounds and proven potent insecticide and repellent respectively. In the search of effective mosquito repellent, different derivatives of DEPA or substituted benzamides were synthesized and their NMR analysis was carried out at low temperature. Sterically Crowded Bis (2-methoxyethyl) substituted Benzamides possess low rotational barrier and are floppy at room temperature. Alkyl arms attached to nitrogen become magnetically nonequivalent even at low temperature. Di ortho Substitution in benzamides enhanced hindered internal rotation and resulted splitting in methylene proton signals. The effect of substitution in benzene ring, on the splitting of methylene proton NMR is very well explained and the complete NMR data of substituted benzamides is described in this study for reference purpose.

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