Convenient procedures for the preparation of representative dialkylborane reagents, diisopinocampheylborane,[1S]-2-diisocaranylborane, 9-borabicyclo [3, 3, 1] nonane, dicyclohexylborane and disiamylborane, using the new, highly reactive N-ethyl-N- isopropylaniline-borane reagent (BACH-EI™) in dioxane and tetrahydrofuran are described.