Chemoselective S-benzylation of indoline-2-thiones using benzyl alcohols

Unprecedented Multicomponent Reaction of Indoles, CS2 and Nitroarenes: Stereoselective Synthesis of (Z)-3-((Arylamino)methylene)indoline-2-thiones

An efficient method for the stereoselective synthesis of (Z)-3-((arylamino)methylene)indoline-2-thiones have been developed via a novel multicomponent reaction of indoles, CS₂ and nitroarenes. A range of functionalized indoline-2-thiones were prepared in moderate to good yields from easily available starting materials. The indoline-2-thione products can be easily derivatized to give biologically active thieno[2,3-b]indole and thiopyrano[2,3-b]indole skeletons in high yields.

Synthesis of tetrahydrothiopyrano[2,3-b]indoles via [3+3] annulation of nitroallylic acetates with indoline-2-thiones

[3+3] annulation of 1,3-binucleophilic indolin-2-thione with 1,3-bielectrophilic nitroallylic acetate via an S_N2-reaction-6-endo-trig cyclization takes place with high regio- and stereoselectivity to afford tetrahydrothiopyranoindoles.

One-pot mild and efficient synthesis of [1,3]thiazino[3,2-a]indol-4-ones and their anti-proliferative activity

One-pot synthesis of [1,3]thiazino[3,2-a]indol-4-one frameworks is developed in aqueous medium and the anti-proliferative activity of the synthesized compounds is evaluated against two triple negative breast cancer cell lines.

Au-Catalyzed Synthesis of Thiopyrano[2,3-b]indoles Featuring Tandem Rearrangement and Hydroarylation

Gold(III)-catalyzed synthesis of 14-π electron heteroaromatic thiopyrano[2,3-b]indole is reported using conjugated enyne tethered indole sulfides, featuring skeletal rearrangement conjoined with intramolecular hydroarylation (via C3-H functionalization of the indole core) and oxidative aromatization. Subsequent Pd-catalyzed C-C coupling resulted in a 16-π electron heteroaromatic isothiochromeno[1,8,7-bcd]indole.

Synthesis of indole-annulated sulfur heterocycles using copper-catalysed C–N coupling and palladium-catalysed direct arylation

A simple and efficient method for the synthesis of biologically relevant 5H-benzo[4,5][1,3]thiazino[3,2-a]indoles and 5,7-dihydroisothiochromeno[3,4-b]indoles has been developed via intramolecular copper catalysed Ullmann-type C–N coupling and palladium catalysed direct arylation.

Mercaptobenzoic acid-palladium(0) complexes as active catalysts for S-benzylation with benzylic alcohols via (η3-benzyl)palladium(ii) cations in water

Mercaptobenzoic acid-palladium(0) complexes show high catalytic activity for S-benzylation with benzylic alcohols via the (η³-benzyl)palladium(ii) cation in water. The catalytic system can be performed using only 2.5 mol% Pd₂(dba)₃ without the phosphine ligand or other additives.

ROMP-derived oligomeric phosphates for application in facile benzylation

The development of new ROMP-based oligomeric benzyl phosphates (OBP(n)) is reported for use as soluble, stable benzylating reagents. These oligomeric reagents are readily synthesized from commercially available materials and conveniently polymerized and purified in a one-pot process, affording bench-stable, pure white, free-flowing solids on multigram scale. Utilization in benzylation reactions with a variety of nucleophiles is reported.