in dichloromethane; pentane T=-40°C; Yields of byproduct given;

in hexane Product distribution;

in hexane T=-78 - 20°C;

in hexane exclusion of moisture, Schlenk technique; addn. of a soln. of borane in hexane to a soln. of arsole in hexane (stirred, 5 min), 2 h (monitored by (11)B NMR); concn., cooled (-78°C), pptn., mixt. of both products, detected by NMR;