Electron-rich aza-aromatic compounds such as indoles is structures of particular interest and importancein organic chemistry. A useful procedure for the preparation of new 3-sulfenyl indole derivatives using S-alkyl or S-arylthiophthalimides as sulfenylating agents and poly(N, N′-dibromo-N-ethyl-naphthyl-2,7-disulfonamide) as novel catalyst is described. The method represents an efficient prepa...

A method for the synthesis of long chain diamines and tetramines starting from natural α-amino acids is reported. Diamines and tetramines were prepared through the Wittig olefination reaction of N-protected amino aldehydes obtained from phenylalanine and lysine. A 1,2,17,18-tetramine was synthesized using (2S)-1-azido-2-[bis(tertbutoxycarbonyl)-amino]-5-oxopentane as key-intermediate compound.

A facile carbohydrate-based highly stereoselective synthetic route has been developed for the cytospolide P (1) from D-ribose for the first time. Key steps of the synthesis include Wittig homologation, regioselective epoxide ring opening, Sharpless asymmetric epoxidation, Evans aldol reaction, and Yamaguchi macrolactonization.

A series of subporphyrin-based fluorescent probes bearing 1-aza-15-crown-5 or 1-aza-18-crown-6 moieties at the meso axial positions were prepared by Pd-catalyzed Buchwald-Hartwig amination reaction corresponding bromosubporphyrins. Both types aza-crown-ether-incorporated subporphyrins in solution and exhibited cation-dependent absorption fluorescence changes. In titration experiments, opposite ...

Since its discovery the rearrangement of R-metalated ethers, particularly the [2,3]-Wittig rearrangement, has been the subject of intensive mechanistic and synthetic investigations.1 Relative to the [2,3]-shift, the [1,2]-Wittig rearrangement has received relatively little publicity. Most studies of the [1,2]-Wittig have been mechanistic in origin, resulting in the widely accepted theory that t...

Efficient syntheses are described for the synthetically important 3-methylquinoline-4-carbaldehydes 6a-h from o-nitrobenzaldehydes 1a-h employing a Wittig-olefination-Claisen-rearrangement protocol. The Wittig reaction of o-nitrobenzaldehydes with crotyloxymethylene triphenylphosphorane afforded crotyl vinyl ethers 2a-h, which on heating under reflux in xylene underwent Claisen rearrangement to...

The aza-Henry reaction of chiral fluoroalkyl α,β-unsaturated N-tert-butanesulfinyl ketoimines and nitromethane was achieved in the presence of 0.2 equivalent of anhydrous potassium carbonate to give the corresponding adducts diastereoselectively in high yields. Transformations which highlighted the synthetic potential of these aza-Henry adducts were also performed.

Starting from acid chlorides, alkynes, tryptamines, and acryloyl chloride, 21 densely substituted tetrahydro-β-carbolines were prepared in a four-component, one-pot reaction. In this study, the aza-Michael addition step to generate intermediate enaminones was optimized presence of ytterbium triflate. Moreover, apart all reactants could be deployed almost equimolar ratios, which increases atom e...