Carbon−Carbon Bond Formation in Regio- and Stereoselective Palladium-Catalyzed Cyclization of Allene-Substituted Conjugated Dienes
作者:Joakim Löfstedt、Johan Franzén、Jan-E. Bäckvall
DOI:10.1021/jo0157324
日期:2001.11.1
Regio- and stereoselective palladium-catalyzed reactions of allene-substituted 1,3-dienes 1 in acetic acid at room temperature lead to cyclization with formation of a carbon-carbon bond between the middle carbon of the allene and the terminal carbon of the 1,3-diene. Two different types of reactions, both that constitute 1,4-carboacetoxylations of the 1,3-diene, have been developed. In one of the reactions
Pd-Catalyzed Borylative Cyclization of Allenynes and Enallenes
作者:Virtudes Pardo-Rodríguez、Juan Marco-Martínez、Elena Buñuel、Diego J. Cárdenas
DOI:10.1021/ol9017694
日期:2009.10.15
Pd-catalyzed cyclization of 1,5- and 1,6-allenynes and 1,5-enallenes with bis(pinacolato)diboron affords synthetically useful allylboronates and alkylboronates under smooth conditions in a formal hydroborylative carbocyclization reaction. One C−C and one C−B bond are formed in a single operation. The reaction outcome implies that different mechanisms operate for the reactions of allenynes and enallenes
Metal catalysis in organic reactions. 17. A nickel-promoted route to substituted allenes by reaction of 1-bromo-1,2-dienes with alkyl metals.
作者:Anna Maria Caporusso、Federico Da Settimo、Luciano Lardicci
DOI:10.1016/s0040-4039(01)80863-7
日期:1985.1
Nickel complexes are found to be catalytically active in the cross-coupling reactions of allenic bromides with alkyl metals to give substitutedallenes in excellent yields. The catalytic process proceeds generally with inversion of configuration in the allenyl moiety.
Reactions of 3-alkyl- and 3,3-dialkyl-1-bromoallenes with organocuprates: Effects of the nature of the cuprate reagent on the regio- and stereoselectivity
作者:Anna Maria Caporusso、Carmela Polizzi、Luciano Lardicci
DOI:10.1016/s0040-4039(00)96867-9
日期:1987.1
Organocuprates induce 1,3- and direct substitution in 3-alkyl- and 3,3-dialkyl-1-bromo-1,2-dienes leading respectively to either terminal acetylenes or allenic hydrocarbons. The nature of the cuprate exerts a prominent role in determining both the regio- and the stereochemistry of these reactions.