Influence of an Equatorial Phenyl Group on Proton Chemical Shifts in Saturated Six-Membered Ring Compounds

K. Pandiarajan and R. Sekar

Department of Chemistry, Annamalsl University, Annamalainagar-608002 India

H-1 NMR spectrum has been recorded for 1- (p-chloropheny1) cyclohexanol (1) at 90 MHz. For t-4'hydroxy- r-2, c-4, c-6-triphenylthiane (2) H-1 NMR spectrum has been recorded at 270 MHZ. Effects of an equatorial phenyl group on the chemical shifts of various ring protons in the chair conformation of six-membered ring systems have been deduced using the chemical shift data for 1 and 2 as well as the reported chemical shift data for c-4-hydroxy-t-3-methyl-r-2, c-6-diphenylthiane (3), 4-D-4-t-buty!thiane (4) and cyclohexane. It has been found that an equatorial phenyl groupdeshields an adjacent axial proton by 0.3 ppm, an adjacent equatorial proton by 0.4 ppm and an axial proton at the γ-carbon(C-4) by 0.2 ppm.

Influence; Equatorial Phenyl Group; Six-Membered