Different type of catalysts used in the Baylis-Hillman reaction

Abstract

The Baylis-Hillman reaction in the present-day version is an atom-economic carbon-carbon bond-forming reaction between the α-position of the activated alkenes and carbon electrophiles under the influence of a catalyst or catalytic system offering diverse classes of densely functionalized molecules.  If the substrate contains both the activated alkene and electrophile components in appropriate positions, there is the possibility of developing an intramolecular version of this reaction leading to the synthesis of carbocyclic or heterocyclic compounds and thus this reaction offers challenges to the design and synthesize the various substrates that can be transferred into diverse classes of carbocyclic and heterocyclic compounds.  Many variations of parameters present in this reaction, infact, generate wide spectra of mechanistic pathways, thereby making understanding the mechanism of this reaction an intellectual challenge.  Most of the Baylis-Hillman reactions are catalyzed by organic compounds like tertiary amines and alkyl(aryl) phosphines, and thus these reactions are referred to as the “organo catalysis reactions”  The importance and growth of the Baylis-Hillman reaction, to a large extent, can also be attributed to the enormous applications of the Baylis-Hillman adducts in synthetic chemistry. The Baylis-Hillman adducts containing a minimum of three functional groups in proximity are valuable substrates for various organic reactions and transformations.

Keywords: Diazabicyclo-(2,2,2)-octane (DABCO),  2,3,4,6,7,8,9,10-Octahydropyrimido[1,2-a]azepine, Indolizine , Quinuclidine, 4-N,N-dimethylamino pyridine (4-DMAP), 4-nitrophenyl acrylamide, Baylis-Hillman reaction, catalysts.