Reactions of (2,3-dimethylenetetramethylene)bis(dipropylborane) with carbonyl compounds

摘要

(2,3-Dimethylenetetramethylene)bis(dipropylborane) (1) prepared by borylation of 2,3-dimethylbutadienediyl dipotassium reacts with ketones to form symmetrical diols in a yield of 46–73. 4+2-Cycloaddition reactions of diborane1with 1,2-dicarbonyl compounds proceed highly stereospecifically, affording onlycis-isomers of 4,5-dimethylenecyclohexane1, 2-diol