TBD-catalyzed α-sulfenylation of cyclic ketones: desymmetrization of 4-substituted cyclohexanones
                                
                                    
                                        作者:Belén Poladura、Ángel Martínez-Castañeda、Humberto Rodríguez-Solla、Carmen Concellón、Vicente del Amo                                    
                                    
                                        DOI:10.1016/j.tet.2012.05.124
                                    
                                    
                                        日期:2012.8
                                    
                                    A low loading of triazabicyclo[4.4.0]dec-5-ene (TBD) catalyzes the alpha-sulfenylation reaction of ketones employing tetramethylthiuram disulfide (TMTDS) as electrophilic reagent. This methodology is mild, effective and straightforward, rendering the desired products in high yield. Prochiral 4-substituted cyclohexanones can be desymmetrized with remarkable diastereoselectivity following this protocol. The dithiocarbamoyl function was shown to be easily removed upon reduction, affording thiols (1-mercaptan-2-ols). (C) 2012 Elsevier Ltd. All rights reserved.