Totalsynthesis of HirsutelloneB has been achieved by a convergent synthetic strategy. This synthesis features direct construction of the highly strained 13-membered macrocycle of HirsutelloneB utilizing the Ullmann-type reaction. To the best of our knowledge, this is the first application of macrocyclization utilizing an intramolecular Ullmann-type reaction between an aliphatic alcohol and aryl
hetero-Michael (DIHMA) reaction to alkynones was applied. The sequence allows for introduction of numerous substituents on the scaffold and for variation of stereochemistry. [5.5]-Spiroketals bearing an additional ketone were obtained in high overall yields. Further diversification was achieved by reduction of the ketone and reductive amination using polymer-supported borohydride, Grignard reaction and conversion
Stereocontrolled synthesis of all of the possible stereoisomers of 3,11-dimethylnonacosan-2-one and 29-hydroxy-3,11-dimethylnonacosan-2-one
作者:Kenji Mori、Satoru Masuda、Toshio Suguro
DOI:10.1016/s0040-4020(01)92448-2
日期:1981.1
possible stereoisomers of 3, 11 - dimethylnonacosan - 2 - one 1 and 29 - hydroxy - 3, 11 -dimethylnonacosan - 2 - one 2 were synthesized from (R)-(+)- citronellic acid as the chiral source. The natural pheromones were shown to be (3S,11S)-1 and (3S, 11S)-2 by direct comparisons.