Stereoinversion of Unactivated Alcohols by Tethered Sulfonamides
作者:Paul T. Marcyk、Latisha R. Jefferies、Deyaa I. AbuSalim、Maren Pink、Mu‐Hyun Baik、Silas P. Cook
DOI:10.1002/anie.201812894
日期:2019.2.4
remains an undeveloped area of organic synthesis. Moreover, catalytic activation of this difficult electrophile with predictable stereo-outcomes presents an even more formidable challenge. Described herein is a simple iron-based catalyst system which provides the mild, direct conversion of secondary and tertiary alcohols to sulfonamides. Starting fromenantioenriched alcohols, the intramolecular variant
N Alkylation of Tosylamides Using Esters as Primary and Tertiary Alkyl Sources: Mediated by Hydrosilanes Activated by a Ruthenium Catalyst
作者:Takashi Nishikata、Hideo Nagashima
DOI:10.1002/anie.201201426
日期:2012.5.29
Select your group: Either a primary or tertiaryalkyl group can be selectively introduced onto the nitrogen atom of tosylamides in a ruthenium‐catalyzed reaction employing hydrosilanes through a judicious choice in the esters that serve as the alkylsource (see scheme; Ts= 4‐toluenesulfonyl). These N‐alkylation reactions are useful for construction of naturally occurring azacyclic skeletons.
Reaction of activated 2,2-dimethylaziridines with Grignardreagents RMgHal in boiling THF can yield the products of normal aziridine ring opening, the rearranged opening products , and the methallylamides (isomers of ). The product distribution depends on R, Hal, and experimental conditions, and very strongly on the nature of the activating group A. It is shown that is opened (reversibly for A = sulfonyl)