Potassium tri(isopropoxy)borohydride sometimes finds use as a source of nucleophilic H: (hydride ion). Suggest a mechanism for

Question:

Potassium tri(isopropoxy)borohydride sometimes finds use as a source of nucleophilic H:– (hydride ion). K+ H-B(OiPr)3 potassium tri(isopropoxy)borohydride

Suggest a mechanism for the substitution reaction in Fig. P18.91 that accounts for the stereochemistry of the reaction. Bu H C=C Br + K+ H-B(OiPr)3 B(OiPr)2 Figure P18.91 Bu H C=C B(OiPr)2 H + K+ Br+ B(OiPr)3