A rapid and stereodefined synthesis of MIDA-boryl vinylsilanes has been achieved through the hydrosilylation of an alkynylboronic ester. The E products which contain a silyl and boryl group can be selectively cross-coupled in a two-step bidirectional sequence to provide a rapid and high-yielding synthesis of complex styrenes.

Two base-mediated cascade rearrangement reactions of diallyl ethers were developed leading to selective [2,3]-Wittig-oxy-Cope and isomerization-Claisen rearrangements. Both diaryl and arylsilyl-substituted 1,3-substituted propenyl substrates were examined, and each exhibits unique reactivity and different reaction pathways. Detailed mechanistic and computational analysis was conducted, which demonstrated that the role of the base and solvent was key to the reactivity and selectivity observed. Crossover experiments also suggest that these reactions proceed with a certain degree of dissociation, and the mechanistic pathway is highly complex with multiple competing routes.

A facile and user-friendly protocol has been developed for the selective synthesis of E-vinyl silanes derived from propargylic alcohols using a PtCl2/XPhos catalyst system. The reaction is generally high yielding and provides a single regioisomer at the β-position with E-alkene geometry. The reaction is extremely tolerant of functionality and has a wide scope of reactivity both in terms of alkynes and silanes used. The catalyst loading has been investigated and it is found that good reactivity is observed at extremely low catalyst loadings. This methodology has also been extended to a one-pot hydrosilylation Denmark-Hiyama coupling.

A rhenium-catalyzed N-selective allylic amination reaction of N-hydroxycarbamates has been developed. This reaction occurs with excellent N/O selectivity and with complete carbon selectivity on the allylic system. The reaction is tolerant of many functional groups and also proceeds with N-hydroxysulfonamides and hydroxamic acids.

A high yielding and completely stereoselective hydrosilylation–Hiyama protocol has been established for the synthesis of highly functionalised E,E-dienes.

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Acids. -In case of Cbz--protected hydroxylamine excellent N/O-selectivities up to 99:1 are observed. -(CHAVHAN, S. W.; MCADAM, C. A.; COOK*, M. J.; J. Org. Chem. 79 (2014) 22, 11234-11240, http://dx.doi.org/10.1021/jo501992p ; Sch. Chem. Chem. Eng., Queen's Univ., Belfast BT9 5AG, UK; Eng.) -U. Scheffler 18-043

An Alkyne Hydrosilylation-Hiyama Coupling Approach to Highly Functionalized 1,3-Dienes. -Both hydrosilylation and Hiyama coupling give E isomers exclusively. -(MCADAM, C. A.; MCLAUGHLIN, M. G.; COOK*, M. J.; Org. Chem. Front. 2 (2015) 5, 510-514, http://dx.doi.org/10.1039/C5QO00002E ; Sch. Chem. Chem. Eng., Queen's Univ., Belfast BT9 5AG, UK; Eng.) -M. Tismer 40-079