ABSTRACTDEVELOPING NEW SYNTHETIC METHODS INVOLVING ORGANOSILANE REAGENTS AND REACTANTSByMaria del Rosario Ivette Amado SierraA novel green method for the reduction of imines to amines by a Pd(OAc)2/PMHS/KFaq system was developed and studied. The optimization studies confirmed the crucial role of the fluoride in activating the PMHS. The addition of PMHS to a Pd(OAc)2 solution results in the formation of polysiloxane encapsulated Pd-nanoparticles, and we were able to confirm the existence of these nanoparticles using transmission electron microscopy (TEM). Additionally 29Si NMR and 19F NMR data obtained from our catalyst system gave some insight into the possible mechanism. Furthermore, the one-pot preparation of several amides via reduction of imines followed by addition of an electrophile was achieved.We were able to develop a new one-pot allylation-hydrostannation sequence of alkynals where the tin byproduct, from the BF3•OEt2–promoted allylation step, was successfully recycled by the introduction of PMHS and catalytic B(C6F5)3 to form Bu3SnH in situ; that was used on the hydrostannation reaction. In addition, our studies were the first to follow BF3•OEt2 mediated allylation by 119Sn and 11B NMR.Finally a new carbon-to-carbon [1,2]-silyl migration was discovered. This migration was triggered by epoxidation using m-CPBA, the cyclopentanones formed have not been reported and contain a silyl group at the position of the carbonyl unit.
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