Synthesis of [6,6,m]-Tricyclic Compounds via [4+2] Cycloaddition with Au or Cu Catalyst
作者:Chang Ho Oh、Juyeon Kang、Seunghwan Ham、Chaehyeon Seong
DOI:10.1055/a-1479-6005
日期:2021.6
We synthesized [6,6,6]- and [6,6,7]-tricyclic compounds via intramolecular [4+2] cycloaddition by gold or copper catalysts. Substrates for cyclization were prepared by coupling reactions between eight types of diyne and four types of aromatic moieties. We have successfully synthesized eleven tricyclic compounds.
An enantioselective oxidative carbocyclization–borylation of enallenes that is catalyzed by palladium(II) and a Brønsted acid was developed. Biphenol‐type chiral phosphoric acids were superior co‐catalysts for inducing the enantioselective cyclization. A number of chiral borylated carbocycles were synthesized in high enantiomeric excess.
A novel and efficient Pd-catalyzed intermolecular [3 + 2] carbocyclization of alkynols and electron-deficient alkynes for the synthesis of halo-cyclopentadienes (Cps) has been developed. The present protocol employs simple propargyl alcohols as the C3 group to participate in the cyclization reaction, providing a highly convenient and atom-economical entry to the halo-cyclopentadiene framework.
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
Convenient synthesis of allenyl esters and amides by palladium catalyzed alkoxy- and amido-carbonylation of allenyl and propynyl halides
作者:Nguyen D. Trieu、Cornelis J. Elsevier、Kees Vrieze
DOI:10.1016/0022-328x(87)80416-3
日期:1987.5
Allenylesters R1R2C=C=C(H)C(O)R (R = OMe) or amides (R = NEt2) are formed with excellent selectivities and in good yields by carbonylation of propynyl and allenyl halides at 1–20 bar CO pressure in benzene, in the presence of MeOH or HNEt2 and 1% of Pd(PPh3)4 or trans-Me2C=C=C(H)Pd(PPh3)2Br. Possible organometallic intermediates are discussed.
通过丙炔基和烯丙基卤化物在1处羰基化,可以形成具有优异选择性和高收率的烯丙基酯R 1 R 2 C = C = C(H)C(O)R(R = OMe)或酰胺(R = NEt 2)。在MeOH或HNEt 2和1%Pd(PPh 3)4或反式-Me 2 C = C = C = C(H)Pd(PPh 3)2 Br存在下,苯中的–20 bar CO压力。讨论了可能的有机金属中间体。