The preparation and reactions of 4-hydroxy-l-methylisonipecotonitrile (I) arc described. The product of the pinaeo! rearrangement of 4-hydroxv-l-methyl-4-piperidyldiphenylcarbinol (V), derived from I, is shown to depend on the reaction conditions. The anomalous reaction of bromine water with l-methyI-4-piperidyIidenediphenylmethane (XII) is discussed.(1) Presented in part before the Division of Organic Chemistry at the 122nd Meeting of the American Chemical Society at Atlantic