Diastereoselective Synthesis and Functionalization of tert-Butylsulfinyl-2-(Chlorodiphenylmethyl)Pyrrolidine

The addition of the carbenoid species (chlorodiphenylmethyl)lithium to chiral N-(4-bromobutylidene)-2-methylpropane-2-sulfinamide affords in high yield (up to 81 %) and excellent diastereoselectivity (>99 : 1) the yet undisclosed tert-butylsulfinyl-2-(chlorodiphenylmethyl)pyrrolidine. Preliminary investigations into SN1 solvolysis reactions of this chloride with different alcohols revealed its potential for further functionalizations leading to differently substituted chiral pyrrolidines, yet showing a relative lability of the tert-butylsulfinyl chiral auxiliary under the employed reaction conditions. Most notably, reactions with sterically hindered alcohols yielded unprecedented derivatives, not easily obtainable using the currently reported procedures for the stereoselective synthesis of diphenylprolinol derivatives.