ChemInform Abstract: Trapping of Carbolithiation‐Derived Tertiary Benzylic α‐Lithio Piperidines with Carbon Electrophiles: Controlling the Formation of α‐Amino Quaternary and Vicinal Stereocenters.

Abstract

Trapping of Carbolithiation-Derived Tertiary Benzylic -Lithio Piperidines with Carbon Electrophiles: Controlling the Formation of -Amino Quaternary and Vicinal Stereocenters. -The carbolithiation of 2-aryl N-Boc-piperidines (I) followed by quenching with MeOH gives rise to 3-alkylated trans-products with high diastereoselectivity. Trapping of organolithium intermediate with dimethyl sulfate leads to 2,2,3-trisubstituted piperidine (V). Carboxylic acid (IX) and esters (XIV) and (XVII) are prepared analogously using dry ice or corresponding chloroformates as electrophiles for the trapping step. -(BENG*, T. K.; FOX, N.; BASSLER, D. P.; ALWALI, A.; SINCAVAGE, K.; SILAIRE, A. W. V.; Org. Biomol. Chem. 13 (2015) 32, 8647-8651, http://dx.doi.org/10.1039/C5OB01371B ; Dep. Chem., Susquehanna Univ., Selinsgrove, PA 17870, USA; Eng.) -R. Staver 50-150