1‐tert‐Butyl‐2‐methyl­phospho­lane–borane and its coupling product 2,2′‐bis(1‐tert‐butyl­phospho­lane–borane)

The title compound, C₉H₂₂BP, and its coupling product, C₁₆H₃₈B₂P₂, were synthesized and their crystal structures analyzed by X‐ray diffraction. The molecular structures clearly explain the stereoselective reaction pathways leading to the products. The average P—B distance and C—P—B angle are 1.929 Å and 114°, respectively.