Crossed prins cyclization

Stemming from the studies on the oxonia [3,3]-sigmatropic alkyl migration of branched homoallylic alcohols by Loh et al. (see Section 8.15, Figure 8.132), the same group had also found that In(OTf)3 catalyzes the formation of tetrahydrofu-rans and tetrahydropyrans from homoallylic alcohols in the presence of aldehydes, developing their initial observations to generate crossed Prins cyclization products... 

Loh et al. developed another crossed Prins cyclization procedure using InCls by careful control of conditions and reactant ratios throughout the reaction [206]. Compared to the earlier requirements for stoichiometric proportions reported by Li et al. [199], the use of InCb was reduced to catalytic levels by using allylchlorosilane as the allylating agent (Figure 8.91). 

Olefin migration Oxidation of alcohols Passerini reaction Pauson-Khand reaction Pinacol cross-coupling Pinner reaction Polymerization of olefins Prins reaction Propargylation Radical addition Radical cyclization Radical substitution Reduction... 

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