1,5-Diborabicyclo[3.3.3]undecane; thermolysis of the product from hydroboration of triallylborane with triethylamine–borane

Abstract

Attempts to reproduce the reported preparation of 1,5-diborabicyclo [3.3.3] undecane 1 through hydroboration of triallylborane with triethylamine–borane, followed by thermolysis, have led to 1,5-dipropyl-1,5-diborocane 2 and other products, but the presence of 1 could not be detected by GC–MS. Treatment of triallylborane with monobromoborane, methanolysis and subsequent thermolysis gave 1,5-dimethoxy-1,5-diborocane 3 which could be converted to 2 by treatment with propylmagnesium bromide.