Cyano compounds are a class of organic compounds with great value. Two different kinds of reactions have been reported using acetone cyanohydrin as reagent and substituted 3,5-dimethyl-N-α,β-unsaturated acyl pyrazole as substrate. The reaction pathway depends on the basic catalysts used when aromatic substituted 3,5-dimethyl-N-α,β-unsaturated acyl pyrazole was used as the substrate. Michael addition reaction occurred in the presence of MgBu 2 with the product yield up to 95%, while alcoholysis reaction of amide occurred in the presence of 1,1,3,3-tetramethylguanidine (TMG), producing β-substituted phenyl cyanoacrylates with 84% yield. However, fatty substituted 3, 5-dimethyl-N-α,β-unsaturated acyl pyrazole and acetone cyanohydrin underwent Michael addition reaction in the presence of MgBu 2 or TMG, the product yield was up to 99%. The possible reaction mechanism when using different basic catalysts was discussed.

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The asymmetric conjugate cyanation reaction of TMSCN with 3,5-dimethyl-N-α,β-unsaturated acylpyrazole catalyzed by magnesium-bisoxazoline complex was studied. The effects of BOX ligand structure, ligand to metal ratio, temperature, solvent, etc. on the reaction were investigated. The results showed that when bis-benzyl substituted bisoxazoline ligand and dibutylmagnesium (molar ratio 2∶1) were used to generate chiral catalyst in situ in 1,2-dichloroethane, the amount of catalyst was 10 mol%, and the reaction temperature was -32 ℃, and the catalytic effect of asymmetric conjugate cyanation reaction was the best. The catalytic method above was applied to the conjugate cyanation reaction of a series of 3,5-dimethyl-N-α,β-unsaturated acyl pyrazole derivatives, most of the corresponding target products could be obtained with more than 90% yield and moderate to good enantioselectivities.