Heniy-Michael reaction

Scheme 2.44 Three-component domino Heniy/Michael reaction catalysed by a combination of a chiral preformed nickel catalyst and a microencapsulated amine catalyst.

If an unsaturated aldehyde was combined with a 1,3-dinitro compound, chiral cyclohexanes were formed by a nitro-Michael/Heniy reaction sequence. Miehael addition followed by double Heniy reaction also led to ehiral eyelohexane derivatives. In another application of the Henry re-aetion, Hayashi used nitroalkenes with pentane-l,5-dial (generated in situ) to form ehiral eyelohexane carboxaldehydes. Chiral cyclopentanes were also eonstrueted in another manner. Enamine-mediated Michael addition of aldehydes to 5-iodo-l-nitropent-l-ene led to an intermediate enamine, which underwent intramoleeular cyclisation via iodide displacement. ... 

Scheme 19.61 Primaiy amine-thiourea catalysed domino Michael-Heniy reaction of 2-aminobenzaldehydes and nitroalkenes.

Scheme 2.23 Pseudo three-component domino Michael-Michael-Heniy reaction catalysed by a combination of chiral diphenylprolinol trimethylsilyl ether and a chiral thiourea.

Scheme 2.34 Tandem Henry-Michael-retro-Heniy reaction catalysed by a chiral cinchona alkaloid thiourea and 1,1,3,3-tetramethyl guanidine.

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