Metalation of diorganostannanes R12SnH2 by lithium diisopropylamide afforded the corresponding (diorganostannyl)lithiums, R12SnHLi. Further reaction with halides led to unsymmetrically substituted alkyl-diorganostannanes, R12R2SnH. In situ stepwise dimetalation of diorganostannanes R12SnH2 gave the expected dialkylation products R12R22Sn with organic halides, aldehydes, and epoxides.