Novel Methodology for the Efficient Synthesis of 3-Aryloxindoles: [1,2]-Phospha-Brook Rearrangement–Palladium-Catalyzed Cross-Coupling Sequence
作者:Masahiro Terada、Azusa Kondoh、Akira Takei
DOI:10.1055/s-0035-1561859
日期:——
A novelmethodology for the efficient synthesis of 3-aryloxindoles from isatin derivatives was developed. The methodology involves the formation of an oxindole having a phosphate moiety at the C-3 position via the [1,2]-phospha-Brook rearrangement under Bronsted base catalysis followed by palladium-catalyzed cross-coupling with aryl boron reagents. The one-pot synthesis of 3-aryloxindoles from isatin
Isothiourea-catalysed enantioselective Michael addition of N-heterocyclic pronucleophiles to α,β-unsaturated aryl esters
作者:Chang Shu、Honglei Liu、Alexandra M. Z. Slawin、Cameron Carpenter-Warren、Andrew D. Smith
DOI:10.1039/c9sc04303a
日期:——
The isothiourea-catalysed enantioselective Michaeladdition of 3-aryloxindole and 4-substituted-dihydropyrazol-3-one pronucleophiles to α,β-unsaturated p-nitrophenyl esters is reported. This process generates products containing two contiguous stereocentres, one quaternary, in good yields and excellent enantioselectivities (>30 examples, up to > 95 : 5 dr and 99 : 1 er). This protocol harnesses the
An organocatalytic asymmetric sulfenylation of 3-aryloxindoles with N-(sulfanyl)succinimides has been developed by using commercially available (DHQD)2PHAL as catalyst. Various chiral 3-benzylthio-, alkylthio-, and arylthio-substituted oxindoles, containing 3,3-disubstituted quarternary carbon stereocenters, could be obtained in high enantioselectivities (85–97% ee). Furthermore, the opposite enantiomers
Highly enantioselective phase-transfer alkylation of 3-substituted-2-oxindoles with activated bromomethanes is disclosed with a broad substrate scope by using bicyclic guanidinium as a catalyst and a Lewis acid as the co-catalyst. The alkylation adducts are versatile intermediates to accomplish the syntheses of pyrroloindolines and furoindolines.
The Palladium Catalyzed Asymmetric Addition of Oxindoles and Allenes: An Atom-Economical Versatile Method for the Construction of Chiral Indole Alkaloids
作者:Barry M. Trost、Jia Xie、Joshua D. Sieber
DOI:10.1021/ja209244m
日期:2011.12.21
The Pd-catalyzed asymmetricallylicalkylation (AAA) is one of the most useful and versatile methods for asymmetric synthesis known in organometallic chemistry. Development of this reaction over the past 30 years has typically relied on the use of an allylic electrophile bearing an appropriate leaving group to access the reactive Pd(π-allyl) intermediate that goes on to the desired coupling product