Pericyclic Cascade with Chirality Transfer: Reaction Pathway and Origin of Enantioselectivity of the Hetero-Claisen Approach to Oxindoles
作者:Nihan Çelebi-Ölçüm、Yu-hong Lam、Edward Richmond、Kenneth B. Ling、Andrew D. Smith、Kendall N. Houk
DOI:10.1002/anie.201105412
日期:2011.11.25
for the chiral auxiliary‐controlled synthesis of 3,3‐disubstituted oxindoles from nitrones and ketenes. The remarkable acyclic 1,6‐stereochemical induction, hitherto unexplained, is rationalized by a stereoselective 3+2 cycloaddition step, which installs the stereochemistry, and a chirality transfer step facilitated by a hetero‐[3,3]‐sigmatropic rearrangement (see picture; PG=protectinggroup).
An Asymmetric Hetero-Claisen Approach to 3-Alkyl-3-aryloxindoles
作者:Nicolas Duguet、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1021/ol901441t
日期:2009.9.3
The reaction of a chiral N-phenylnitrone derived from Garner's aldehyde with alkylarylketenes generates 3-alkyl-3-aryloxindoles directly in excellent yields and with good to excellent levels of enantioselectivity (up to 90% ee).
An asymmetric pericyclic cascade approach to 3-alkyl-3-aryloxindoles: generality, applications and mechanistic investigations
作者:Edward Richmond、Kenneth B. Ling、Nicolas Duguet、Lois B. Manton、Nihan Çelebi-Ölçüm、Yu-Hong Lam、Sezen Alsancak、Alexandra M. Z. Slawin、K. N. Houk、Andrew D. Smith
DOI:10.1039/c4ob02526a
日期:——
The reaction of l-serine derived N-arylnitrones with alkylarylketenes generates 3-alkyl-3-aryloxindoles in good yields and excellent enantioselectivities.