An alkyne hydrosilylation–Hiyama coupling approach to highly functionalised 1,3-dienes

Abstract

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

A Dual CuH- and Pd-Catalyzed Stereoselective Synthesis of Highly Substituted 1,3-Dienes

“…18,24,26,28 To avoid the formation of isomeric product mixtures, transition-metal catalyzed cross-coupling utilizing preformed organometallic reagents and vinyl (pseudo)halides has emerged as a practical route to stereoselectively synthesize dienes (Figure 1B). [29][30][31][32][33][34] In these processes, the geometry of the diene product is dictated…”

“…Due to the utility of 1,3-dienes in organic synthesis, a variety of strategies to access these compounds have been developed. , Olefination of carbonyl compounds with stoichiometric allyl nucleophiles has been widely employed in the synthesis of conjugated dienes; − however, the products are generally obtained as inseparable E/Z mixtures (Figure A). , Although considerable advances have been made toward stereoselective olefination of carbonyl substrates, most methods to access 1,3-dienes result in the E,E- isomer. ,,, To avoid the formation of isomeric product mixtures, transition-metal-catalyzed cross-coupling utilizing preformed organometallic reagents and vinyl (pseudo)­halides has emerged as a practical route to stereoselectively synthesize dienes (Figure B). − In these processes, the geometry of the diene product is dictated by the stereochemistry of the coupling partners. Complementary approaches to prepare 1,3-dienes, including C–H activation of olefin starting materials, , rearrangements of allenes or alkynes, and ene-yne metathesis of acyclic precursors, , have also been developed. , …”

Modern Synthetic Methods for the Stereoselective Construction of 1,3-Dienes

“…McAdam and co-workers developed an hydrosilylation methodology to form vinylsilanes from propargylic alcohols using commercially available benzyldimethylsilane; the resulting vinylsilanes are very stable and can undergo simple activation with TBAF under Trost-type conditions [ 60 , 61 ]. Subsequently, these authors developed a methodology for the formation of highly functionalised 1,3-dienes based on the hydrosilylation–Hiyama protocol ( Scheme 9 ) [ 62 ]. Thus, hydrosilylation of 1-ethynylcyclohexan-1-ol afforded the corresponding vinylsilane in excellent yield and total E selectivity.…”

Nickel- and Brønsted Acid-Catalyzed Redox-Neutral Coupling of 1,3-Dienes and Aldehydes for Synthesis of Dienols

“…Dienols are important structural motifs that not only widely exist in numerous bioactive compounds (Figure 1a), [1][2][3][4] but also act as versatile synthons in Diels-Alder reactions 5,6 and other reactions. 7,8 Although numerous methods have been developed to synthesize them, for example Wittig reaction and cross-coupling reactions, [9][10][11][12][13][14][15] carbonyl addition reactions that join diene precursors with carbonyl compounds would undoubtedly be more attractive pathways because of easier availability of carbonyls. [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] The first generation of methods through this pathway used moisture-sensitive dienyl metals as addition agents.…”