Claisen rearrangement solved problems

There is a change in the regiochemical course for Claisen rearrangement" of a letrahydropyridyl allyl ether by BFj-OEtj. The problem in stereocontrol of the aldol reaction involving cyclic ketones and aldehydes can be solved by way of the rearrangement of hydroxyalkyl epoxides." Ultimately, it rests on the proper choice of the haloalkenes. 

Microwave irradiation strongly enhances the rate of Claisen rearrangement. This helps in solving the problem of the long-term heating under conventional conditions. The yield of rearranged produets in classical method is about 85% in 6 h where as it was inereased to 92% in 6 min by using N,N-dimethylformamide as solvent under mierowave irradiation. 

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