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.