Stereoselective Ring Opening Reaction of 2-cycloalkanols Mediated by N-Chlorosuccinimide and Triethylamine

Article abstract of DOI:10.1021/jo00383a015

Treatment of 2-<1-(phenylthio)benzyl>cyclohexanol (2c) with N-chlorosuccinimide (NCS) and triethylamine gave various product 3-6c depending on reaction conditions.Exclusive ring-opening reaction of 2c was achieved by temperature control.Thus, five-, six-, and seven-membered cycloalkanols 2a-g were converted to ω-oxo-α,β-unsaturated sulfides 6a-g in good yields.The stereochemistry of the reaction was determined by using four diastereomers 10a-d; trans-erythro-10b and cis-threo-10c afforded (E)- and (Z)-heptenals 6c as a single isomer, respectively, while a mixture of the two isomers 6c (60:40 or 40:60) was obtained from trans-threo-10a and cis-erythro-10d.Allyl-, propargyl-, and <(trimethylsilyl)methyl>cyclohexanols 23, 25, and 27 also yielded corresponding unsaturated sulfides 24, 26, and 28.