of synthetically useful reactions of 2-trimethylsilylmethyl-1,3-butadiene (7) are discussed. Reactions of 7 with acid chlorides, aldehydes, ketones and acetals activated by a Lewis acid give isoprenylated compounds, while 7 undergoes the Diels-Alderreaction with dienophiles. High regiospecificity of the reaction qualifies 7 for a versatile building block of terpene synthesis.
methods for oxidative rearrangement of tertiary allylic alcohols to β-substituted α,β-unsaturated carbonyl compounds employing oxoammonium salts are described. The methods developed are applicable to acyclic substrates as well as medium membered ring substrates and macrocyclic substrates. The counteranion of the oxoammonium salt plays crucial roles on this oxidative rearrangement.
Highly regioselective diels-alder reactions of 2-trimethylsilylmethyl- 1,3-butadiene catalyzed by a lewis acid and applications to syntheses of terpenes
2-Trimethylsilylmethyl-1,3-butadiene undergoes highly regioselective Diels-Alderreactions with dienophiles such as acrolein and methyl vinyl ketone catalyzed by aluminum chloride in which the “para” isomers are obtained almost exclusively. The adducts are converted readily to a variety of naturally occurring mono and sesquiterpenes.
Préparation de cétones et d'alcools insaturés a partir de la méthylvinylcétone. Une synthése simple et efficace d'alcools isopréniques
作者:R. Bloch
DOI:10.1016/s0040-4020(01)91839-3
日期:1983.1
The preparation of olefinic ketones and alcohols by means of a retro Diels-Alder reaction is described. This process has been applied to high yield syntheses of linalool 6e, nerolidol 6f and the sesquiterpene alcohol 10 recently isolated from the alga Laurencia nidifica.
A practical and environmentally friendly method for oxidative rearrangement of five- and six-membered cyclic tertiary allylic alcohols to beta-disubstituted alpha,beta-unsaturated ketones by the IBX/DMSO reagent system is described. Several conventional protecting groups (e.g., Ac, MOM, and TBDPS) are compatible under the reaction conditions prescribed.