A ring-closing metathesis approach to the bicyclo[4.3.1]decane core of caryolanes
作者:William P.D. Goldring、Warren T. Paden
DOI:10.1016/j.tetlet.2010.11.138
日期:2011.2
A synthesis of highly substituted and sterically congested bicyclo[4.3.1]decenes, a structure embedded in the core 4,7,6-tricyclic system of natural caryolanes, was successfully achieved via a ring-closing metathesis (RCM) reaction of syn-1,3-diene substituted cyclohexanols. The construction of the diene substrates, starting from 4-acetoxy-3-methyl-2-cyclohexen-1-one, employed diastereoselective copper-mediated
Synthesis of optically active cyclohexenol derivatives via enzyme catalyzed ester hydrolysis of 4-acetoxy-3-methyl-2-cyclohexenone
作者:Magnus Polla、Torbjörn Frejd
DOI:10.1016/s0040-4020(01)86539-x
日期:1991.7
The opticallyactive cyclohexenol derivatives 9a–9d, and 10a–10c are synthesized from (−)-6, which is obtained by enzymatic esterhydrolysis of racemic 8. Attempts towards the synthesis of the taxane skeleton are described.
Enantioconvergent Access to the Enantiomerically Pure Building Blocks (+)- or (-)-4-Hydroxy-3-methyl-2-cyclohexenone Using a Chemoenzymatic Process
作者:Gérard Audran、Honoré Monti、Elie Palombo
DOI:10.1055/s-2006-926258
日期:——
A convenient chemoenzymatic enantioconvergent access to enantiomerically pure (+)- or (-)-4-hydroxy-3-methyl-2-cyclohexenone is described using a one-pot two-step kinetic resolution-stereoinversion protocol followed by hydrolysis. The key step of the sequence is the spontaneous elimination of an undesired stereocenter. The choice between enzymatic acyl transfer or ester alcoholysis of the corresponding racemic starting material, together with the selectivity of a lipase, determines the absolute configuration of the desired single enantiomer.
Total Synthesis of (+)-Mutilin: A Transannular [2+2] Cycloaddition/Fragmentation Approach
作者:Han Chen、Zesheng Li、Peng Shao、Haosen Yuan、Si-Cong Chen、Tuoping Luo
DOI:10.1021/jacs.2c06934
日期:2022.8.31
enantioselective total synthesis of the diterpenoid (+)-mutilin is described. Following a Claisen rearrangement approach to construct the 6,9-bicycle, a transannular [2+2] photocycloaddition and the ensuing ring-opening reaction were implemented to forge the characteristic 5–6–8 propellane-like skeleton. Subsequent late-stage alkylations and reduction completed the synthesis.
Concise Total Syntheses of the Sesquiterpenoids (−)-Homalomenol A and (−)-Homalomenol B
作者:Edward Piers、Renata M. Oballa
DOI:10.1021/jo961605+
日期:1996.1.1
The conjugate additions of the organocopper(I) reagents 22 and 27 to the enantiomerically homogeneous bicyclic enone 4 provided, after epimerization (NaOMe, MeOH) of the resultant product mixtures and appropriate chromatographic separations, the bicyclo[4.3.0]nonan-2-ones 24 and 28. Compounds 24 and 28 were readily converted, via two synthetic steps in each case, into,the sesquiterpenoids (-)-homalomenols B (2) and A (1), respectively.