Abstract
Ene-type chloride (5 a) was prepared with trichloroisocyanuric acid as a chlorination reagent from pentenylchromanol (3), obtained from myrcene and 2, 3, 5-trimethylhydroquinone in 3 steps. Chloride (5 a) reacted with 3, 7-dimethyloctylmagnesium bromide in the presence of CuCl (I) as the catalyst in THE to afford mixture consisting of SN2' type cross coupling products (7 a) and (8 a) with high regioselectivity. Compounds (5 b-e) reacted with the Grignard reagent in the presence of CuCl (I) to give SN2' type cross coupling products (7) and (8) with high regioselectivity Table-1. dl-α-Tocopherol was prepared in good yields by the hydrogenation of compounds (7 a) and (8 a).