Bayliss-Hillman

There has been a number of developments in the use of salicylaldehydes as precursors of both chromenes and chromans. Alkenes activated by acyl, formyl, nitrile and phenylsulfonyl groups react with 2-hydroxybenzaldehydes and 2-hydroxy-1-naphthaldehyde under Bayliss-Hillman conditions to yield 3-substituted chromenes via the in situ dehydration of the initially formed chroman-4-ol <02JCS(P1)1318>. In like manner, P-nitrostyrenes yield 2- and 2,2-substituted derivatives of 3-nitrochromenes <02H(57)1033>. A simple route to 2-phenyl-2H-chromenes starting from salicylaldehyde and utilising a Pd(0)-catalysed cyclisation of an allylic acetate has been described <02SC3667>. 

Auge,J. Lubin, N. Lubineau, A., Acceleration in water of the Bayliss-Hillman reaction. Tetrahedron Lett. 1994, 35, 7947. 

Nazarov, I. N. Torgov, I. B. Terekhova, L. N. Bull. Acad. Sci. (USSR) 1942, 200. I. N. Nazarov (1900—1957), a Soviet Union Scientist, discovered this reaction in 1942. It was said that almost as many young synthetic chemists have been lost in the pursuit of an as)Tnmetric Nazarov cychzation as of the Bayliss—Hillman reaction. 

The Bayliss-Hillman reaction is commonly used for the coupling of Michael acceptors with aldehydes to give /3-hydroxy-a-methylene esters/ketones/nitriles. The use of imines in place of aldehydes provides entry to the corresponding /3-amino products. Examples of the asymmetric Bayliss-Hillman reaction with imines are very rare. Aggarwal and co-workers have shown that indium(III) triflate in combination with 3-hydroxyquinuclidine (3-HQD) catalyzes the reaction of enantiomerically pure N-p-toluenesulfinimine with methyl acrylate in an asymmetric Bayliss-Hillman reaction (eq 15). Higher diastereoselectivity was observed in the reaction of A-tert-butanesulfinimines, however, the yields were much poorer. ... 

While high-pressure reactions typically require specialized equipment, a Bayliss-Hillman reaction between p-bromohenzaldehyde and methyl acrylate has been induced by the pressure created as water freezes (2 kbar). The reaction is performed in a test tube placed in a water-filled sealed autoclave in a household refrigerator at -20°C. An 86% yield was obtained in this manner compared to 65% yield at 1 atm [17]. 

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