(Z)-Selective Enol Triflation of α-Alkoxyacetoaldehydes: Application to Synthesis of (Z)-Allylic Alcohols via Cross-Coupling Reaction and [1,2]-Wittig Rearrangement

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. , …”

C−C Bond Formation of Benzyl Alcohols and Alkynes Using a Catalytic Amount of KOtBu: Unusual Regioselectivity through a Radical Mechanism

“…Another pathway we considered involves the reaction of benzyl alcohol and phenylacetylene to give styryl ether I , which could undergo a 1,2‐Wittig‐type rearrangement to give an allylic alcohol II that can isomerize to the ketone product 1 (Scheme ). However, this possibility was ruled out since no conversion of the styryl ether I was observed when heated at reflux in toluene in presence of KO t Bu (10 mol %).…”

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 by the stereochemistry of the coupling partners. Complementary approaches to prepare 1,3-dienes, including C-H activation of olefin starting materials, [35][36] rearrangements of allenes or alkynes, 37 and ene-yne metathesis of acyclic precursors, [38][39] have also been developed.…”