Regioselective α-Cyanation of Unprotected Alicyclic Amines
作者:Fuchao Yu、Daniel A. Valles、Weijie Chen、Scott D. Daniel、Ion Ghiviriga、Daniel Seidel
DOI:10.1021/acs.orglett.2c02148
日期:2022.9.9
Secondary alicyclic amines are converted to α-aminonitriles via addition of TMSCN to their corresponding imines, intermediates that are produced in situ via the oxidation of amine-derived lithium amides with simple ketone oxidants. Amines with an existing α-substituent undergo regioselective α′-cyanation even if the C–H bonds at that site are less activated. Amine α-arylation can be combined with α′-cyanation
Stereochemical course of the reductive spiroannulations of N-Boc and N-benzyl 2-cyanopiperidines
作者:Scott A. Wolckenhauer、Scott D. Rychnovsky
DOI:10.1016/j.tet.2005.01.099
日期:2005.3
The stereochemical outcome of spiroannulations of N-protected 2-lithiopiperidines (generated by lithium di-tert-butyl biphenylide (LiDBB) mediated reductive lithiation of 2-cyanopiperidines) was investigated using deuterium labeled side-chains containing phosphate leaving groups. High stereoselectivity was observed when benzyl (Bn) protected 2-cyanopiperidines were employed, while tert-butoxycarbonyl
The stereochemicalcourse of electrophilic substitution of α-nitrile metallocarbanions generated by deprotonation from N-Boc- and N-carbamoyl-2-cyano-6-methylpiperidines was investigated. Deprotonation in the presence of an electrophile taking advantage of the high acidity of α-nitrile protons allowed examination of the effects of a chelating group on the nitrogen atom, a countercation, and the reactivity