Chiral Aminated α-Methylenebenzocycloalkenes from o-Bromoaryl Aldehydes and Ketones

Chiral tert-butylsulfinyl imines 3, which are easily prepared from the corresponding bromo carbonyl compounds 1 and tert-butanesulfinamide (2), undergo a diastereoselective allylation by using indium metal and allyl bromide to give the corresponding homoallyl sulfinylamines 4. Treatment of compounds 4 with a catalytic amount of palladium acetate and triphenylphosphane gives exo-methylene-substitutedsulfinylamino)benzocycloalkenes 5 (five- to seven-membered rings) that are easily deprotected with hydrochloric acid to give chiral primary amines 6.The authors thank the Spanish Ministerio de Ciencia e Innovación (MICINN) (grant number CTQ2007-65218), the Consolider Ingenio (grant numbers 2010-CSD-2007-00006 and CTQ2011-24165), the Generalitat Valenciana (grant number PROMETEO/2009/039), the Fondos Europeos para el Desarrollo Regional (FEDER), and the University of Alicante for the financial support