Synthesis of Cyclobutene-Fused Eight-Membered Carbocycles through Gold-Catalyzed Intramolecular Enyne [2+2] Cycloaddition
作者:Tomohiro Iwai、Masahiro Ueno、Hiori Okochi、Masaya Sawamura
DOI:10.1002/adsc.201701193
日期:2018.2.15
Cationic gold(I) complexes with hollow‐shaped triethynylphosphine ligands efficiently catalyzed intramolecular [2+2] cycloaddition of 1,9‐enynes to afford cyclobutene‐fused eight‐membered carbocycles that were difficult to synthesize by other catalytic systems. Various 1,9‐enynes with carbon linkers with or without a fused ring underwent efficient [2+2] cycloaddition with 5 mol% of the Au catalyst
具有空心三乙炔基膦配体的阳离子金(I)配合物可有效催化1,9-炔烃的分子内[2 + 2]环加成反应,从而制得环丁烯稠合的八元碳环,这些碳环很难被其他催化系统合成。在室温下,在室温下,在CH 2 Cl 2中,各种带有碳接头的带有或不带有稠合环的1,9-烯类化合物进行有效的[2 + 2]环加成反应,加入5 mol%的带有三芳基甲基封端的三乙炔膦的Au催化剂。 MS 4A作为添加剂。具有挑战性的具有完全饱和的无环碳连接基的1,9-烯炔底物在缺少MS 4A的情况下于60°C在ClCH 2 CH 2 Cl中经历了八元环形成,形成了单环1,3-二烯作为主要产物。