Palladium-catalyzed carbonylative cyclization of o-allylbenzyl halides to produce benzo-annulated enol lactones and/or bicyclo[3.3.0]hept-3-en-6-ones. An efficient route to U-68,215
摘要:
Treatment of omicron-allylbenzyl halides with CO in the presence of 1.5-2.0 equiv of a base, such as NEt3, and a catalytic amount of a palladium complex, such as Cl2Pd(PPh3)2, provides a 2,3,3a,4-tetrahydro-2-oxonaphthyl[2,3-b]furans and/or cyclovutanone derivatives tentatively identified as 2,2a,7,7a-tetrahydro-1H-cyclobut[a]inden-2-ones.
Palladium-catalyzed carbonylative cyclization via trapping of acylpalladium derivatives with internal enolates. Its scope and factors affecting the C-to-O ratio
摘要:
The Pd-catalyzed carbonylative cyclization reaction involving omega-acyl-substituted acylpalladium derivatives can proceed via intramolecular trapping with either C- or O-enolates; the preferential formation of either 5- or 6-membered rings dictates the C-to-O ratio in the trapping with enolates.