The synthesis and rearrangement of the cyclobutyl methanol 4 is described. The synthesis has been achieved by addition of the Grignard reagent 16 to the bicyclic ketone 22. Experimental procedures for the preparation of both compounds are given. Upon treatment with trifluoroacetic acid and subsequent reduction, 4 yields the norbornanes 24 and 25 and (±)-cerapicol (8). Some consequences concerning the
A new asymmetric synthesis of (+)-grandisol via a kinetic resolution
作者:David P.G. Hamon、Kellie L. Tuck
DOI:10.1016/s0040-4039(99)01605-6
日期:1999.10
A novel approach to the asymmetric synthesis of (+)-grandisol involves the use of catalytic kinetic resolution of a primary allylic alcohol. The allylic alcohol is prepared in 4 steps from simple achiral materials and the resolved alcohol (95%e.e.) is reduced in 2 steps to the corresponding methyl alkene. This alkene is converted to (+)-grandisol (95%e.e.).
Practical preparation of bicyclo[3.2.0]hept-3-en-6-ones and its utilisation in stereoselective total synthesis of grandisol and lineatin via a versatile intermediate.
devised for racemic grandisol and lineatin, two important components of pheromonic blends. They are based on the utilisation of 1,4-dimethylbicyclo[3.2.0]hept-3-en-6-one as a pivotal intermediate. This compound, as well as other bicyclo[3.2.0]hept-3-en-6-ones, are now easily available by a practical bicyclization of the corresponding 3-hydroxy-6-alkenoic acids.