Photochemical Access to Tetra- and Pentacyclic Terpene-like Products from R-(+)-Sclareolide
摘要:
Fused tetracyclic oxetanes 4, highly substituted cyclobutenes 6, and the pentacyclic derivatives 7 and 8 were obtained by irradiation of derivatives 3 that were prepared from commercial R-(+)-sclareolide (1) in three steps. Compounds 4 are formed through a Paterno-Buchi reaction, while tricyclic derivatives 6 are the fragmentation products of the first formed oxetanes. In clear contrast, cyclopentenyl and 3-furyl derivatives, 3e and 3f, gave the [2+2] adducts, namely pentacyclic derivatives 7 and 8. All the reported reactions are totally regio- and stereoselective, with the exception of the cyclization of furyl derivative 3f, which gave the mixture of both the crossed (7b) and the right (8) isomers.
Photochemical Access to Tetra- and Pentacyclic Terpene-like Products from R-(+)-Sclareolide
摘要:
Fused tetracyclic oxetanes 4, highly substituted cyclobutenes 6, and the pentacyclic derivatives 7 and 8 were obtained by irradiation of derivatives 3 that were prepared from commercial R-(+)-sclareolide (1) in three steps. Compounds 4 are formed through a Paterno-Buchi reaction, while tricyclic derivatives 6 are the fragmentation products of the first formed oxetanes. In clear contrast, cyclopentenyl and 3-furyl derivatives, 3e and 3f, gave the [2+2] adducts, namely pentacyclic derivatives 7 and 8. All the reported reactions are totally regio- and stereoselective, with the exception of the cyclization of furyl derivative 3f, which gave the mixture of both the crossed (7b) and the right (8) isomers.
Synthesis of α-Onoceradiene-like Terpene Dimers by Intermolecular Metathesis Processes
作者:María C. de la Torre、Antonio M. Deometrio、Elsa Álvaro、Isabel García、Miguel A. Sierra
DOI:10.1021/ol052680m
日期:2006.2.1
New alpha-onoceradiene analogues having a terpene homodimer skeleton are accessible from Weinreb's amide 2 derived from commercial (R)(+)-sclareolide using an intermolecular metathesis reaction as the key step to build the linker joining both terpene moieties.
Photochemical Access to Tetra- and Pentacyclic Terpene-like Products from <i>R</i>-(+)-Sclareolide
作者:María C. de la Torre、Isabel García、Miguel A. Sierra
DOI:10.1021/jo034177y
日期:2003.8.1
Fused tetracyclic oxetanes 4, highly substituted cyclobutenes 6, and the pentacyclic derivatives 7 and 8 were obtained by irradiation of derivatives 3 that were prepared from commercial R-(+)-sclareolide (1) in three steps. Compounds 4 are formed through a Paterno-Buchi reaction, while tricyclic derivatives 6 are the fragmentation products of the first formed oxetanes. In clear contrast, cyclopentenyl and 3-furyl derivatives, 3e and 3f, gave the [2+2] adducts, namely pentacyclic derivatives 7 and 8. All the reported reactions are totally regio- and stereoselective, with the exception of the cyclization of furyl derivative 3f, which gave the mixture of both the crossed (7b) and the right (8) isomers.