Synthesis of optically active forms of ipsdienol and ipsenol
作者:K. Mori、T. Takigawa、T. Matsuo
DOI:10.1016/s0040-4020(01)93705-6
日期:1979.1
(R)-(-)-Ipsdienol 1″ and its antipode 1' were synthesized from (R)-(+)-glyceraldehyde acetonide and (R)-(+)-malic acid, respectively. This established the S-configuration of the naturally occurring (+)-ipsdienol. A new synthesis of (R)-(+)-ipsenol 2″ and its antipode 2' was also described. Chiral epoxides were shown to be useful intermediates for the synthesis of these chiral alcohols.
The BINOL‐derived chiral phosphoric acid (R)‐TRIP is utilized as an organocatalyst in the asymmetric isoprenylboration reaction of aldehydes, wherein hydrogen‐bond interactions play a key role in the control of enantioselectivity. A wide arrays of enantioenriched dienyl homoallyl alcohols, including two natural products (−)‐Ipsdienol and (−)‐Ipsenol, have been successfully constituted. The synthetic
catalytic asymmetric allylic transfer reactions of achiral aldehydes with 2-ethynyl- and 2-ethenyl-2-propenylstannane promoted by BINOL-TiIV complex with synergetic reagent are achieved for the synthesis of homoenynyl- and dienyl alcohols with high levels of enantioselectivity. The range of enantioselectivity is 84−99% ee with good chemical yields. The application of catalytic asymmetric dienylation
Chiral synthesis VIA organoboranes. 26. An efficient synthesis of isoprenyl derivatives of borane - valuable reagents for the isoprenylboration of aldehydes. A convenient route to both enantiomers of ipsenol and ipsdienol in high optical purity
作者:Herbert C. Brown、Ramnarayan S. Randad
DOI:10.1016/s0040-4020(01)85575-7
日期:1990.1
namely metallation of isoprene with potassium 2,2,5,5-tetramethylpiperidide followed by sequential treatment with B-methoxydialkylborane and boron trifluoride-etherate. These reagents are used for the convenient isoprenylation of aldehydes. Reaction of isovaleraldehyde and β, β-dimethylacrolein with B2'isoprenyldiisopinocampheylborane provides both ipsenol and ipsdienol, respectively in 65% yields and 96%
A six step synthesis of S-(−)-ipsenol, a constituent of the sex pheromone of the bark beetle, from lacticacid employs an asymmetric aldol condensation and a novel molybdenum catalyzed elimination of an allyl ester as key steps.