The reagent 3-chloro-1-lithiopropene (4) can be generated by treating 1-bromo-3-chloropropene with t-BuLi. It is unstable but if generated at low temperature in the presence of alkylboronic esters, such as 3, is trapped in situ to give rearrangement products 2, which on oxidation give 3-alkylprop-1-en-3-ols in good yields. The reaction works for primary, secondary, benzylic, and even tertiary a...

Novel unsaturated ethers were synthesised in good yields starting from sucrose,using a two-step mild and efficient procedure based on the Gassman method, which consists in forming a vinyl group by the elimination of ethanol from mixed acetals with trimethylsilyl trifluoromethanesulfonate in the presence of alkyl amines. Mixed acetals are readily obtained from the corresponding alcohols and ethy...

Oxetanes offer exciting potential as structural motifs and intermediates in drug discovery and materials science. Here an efficient strategy for the synthesis of oxetane rings incorporating pendant functional groups is described. A wide variety of oxetane 2,2-dicarboxylates were accessed in high yields, including functionalized 3-/4-aryl- and alkyl-substituted oxetanes and fused oxetane bicycle...

This paper presents an application of plastic evolu tion to design a new chemical index (the coordination index , ( .) that permits molecular characterizati on. Ie is applied to homologous series of phenyl alcohols and 4-alkylanilines. and compared to charge indices for dipole mome nt. The parameters needed to calcu late Ie are minus the standard enthalpy of formation T, molecu lar surface area...

12-Carboxamido- and 12-carboxyl-11-spirostenes were synthesized from the corresponding 12-iodo-11-ene derivative in palladium-catalyzed carbonylation reactions under mild reaction conditions. The synthesis of the iodo-alkene substrate is based on the transformation of the 12-keto derivative (hecogenin) to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl gu...

Gel-permeation chromatography on Sephadex LH-20, using ethanol as eluent, permits the resolution of neutral hydroxy lipids according to molecular size. The influence of molecular shape, functional groups, chain lengths, and degree of unsaturation, as well as the effect of the eluent on the elution pattern are discussed. The usefulness of the method for the separation of classes of hydroxy lipid...

The impressive surface activity of silicones can be enhanced by the incorporation of hydrophilic organic functional groups and polymers. Traditional routes to such compounds, which typically involve platinum-catalyzed hydrosilylation, suffer from incompatibility with certain functional groups. B(C(6)F(5))(3)-catalyzed condensation of hydrosilanes with alkoxysilanes offers new opportunities to p...