Bromide bromodimethyl sulfonium

Various carbonyl compounds were efficiently converted into the corresponding 1,3-dithiolanes using triethyl orthoformate as a water scavenger and (bromodimethyl)sulfonium bromide as an efficient catalyst under solvent-free conditions <2004EJ02002>. This protocol can be applied for the chemoselective protection of aldehydes in the presence of ketones on a large scale (Equation 73). 

Keywords acetalization, thioacetalization, (bromodimethyl)sulfonium bromide... 

For multicomponent synthesis of homoallylic amines using all-yltributylstannane instead of allyltrimethylsilane and catalyzed hy different species, see Polymer-bound-Yb salts (polyfluoro-alkyl sulfonic acids) (a) Y. Yin, G. Zhao, G.-L. Li, Tetrahedron 2005, 61, 12042-12052. Synthesis of polystyrene-bound per-fluoroaUcyl sulfonic acids and the application of their ytterbium salts in multicomponent reactions (MCRs). (Bromodimethyl) suhbnium bromide (Me S BrBr) (b) B. Das, B. Ravikanth, P Thirupathi, B. Vittal Rao, Tetrahedron Lett. 2006, 47, 5041-5044. (Bromodimethyl)sulfonium bromide catalyzed efficient multicomponent one-pot synthesis of homoaUyhc amines. 

Catalyst (Bromodimethyl)sulfonium bromide [Me2S BrBr ]... 

Keywords o-Phenylenediamines, ketones, (bromodimethyl)sulfonium bromide, solvent-free, room temperature, condensation, 1,5-benzodiazepines... 

A mixture of o-phenylenediamine (1 1 mmol) and ketone (2 2.2 mmol) was well stirred with (bromodimethyl) sulfonium bromide (10 mol%) at room temperature for 1 h so as to complete the reaction as monitored by TLC. The reaction mixture was then quenched with 5 mL of water and extracted with EtOAc (3x5 mL). The extract was concentrated and the residue was subjected to column chromatography over silica gel using EtOAc-hexane (1 4) as eluent to afford pure 1,5-benzodiazepine (3). Physical and spectral data of all the isolated products were found to be in accordance with the known compounds reported in literature. 

Das, B., Ramu, R., Ravikanth, B., and Saidi Reddy, V. (2006). (Bromodimethyl)sulfonium bromide An efficient catalyst for solvent-free synthesis of 1,5-benzodiazepines. /. Mol. Catal. A Chem., 246, 76-78. 

SCHEME 4.101 Preparation of a-aminophosphonate using (bromodimethyl)sulfonium bromide as the catalyst [171]. 

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