building blocks from α‐sulfonyl nitriles, circumventing traditional base‐mediated α‐alkylation conditions and strong single electron donors. The reaction tolerates numerous functional groups including free alcohols, esters, amides, and it can be applied also to the α‐desulfonylation of ketones. In addition, a one‐pot desulfonylative alkylation is demonstrated. Preliminary mechanistic studies indicate a catalyst‐dependent
Chemoselective Alkylations with <i>N</i>- and <i>C</i>-Metalated Nitriles
作者:Xun Yang、Dinesh Nath、Fraser F. Fleming
DOI:10.1021/acs.orglett.5b02481
日期:2015.10.2
electrophilic alkylations. N-Lithiated or C-magnesiated nitriles can be prepared from the same nitrile precursor and selectively reacted with a 1:1 mixture of methyl cyanoformate and benzyl bromide or bifunctionalelectrophiles through chemoselective attack onto either an alkyl halide or a carbonyl electrophile. A mechanistic explanation for the chemoselectivity preferences is provided that rests on the structural
Nitrile Alkylations through Sulfinyl-Metal Exchange
作者:Dinesh Nath、Fraser F. Fleming
DOI:10.1002/anie.201105630
日期:2011.12.2
Triple alkylation: Phenylsulfinyl‐ and phenylthioacetonitrile can function as trianion equivalents of acetonitrile by sequential alkylation and sulfinyl–metal exchange (see scheme; mCPBA=meta‐chloroperoxybenzoic acid). The metalated nitriles alkylate a range of electrophiles to obtain nitriles with quaternary centers. The sulfinyl–metal exchange proceeds under very mild conditions and has a high functional‐group