Dendritic catalysis in asymmetric synthesis

In this review, we have focused our attention on the application of dendrimers as asymmetric catalyst in organic synthesis, which appeared in the literature. Dendrimers have been identified as a promising candidate for catalysis application. The combination of high surface area and high solubility makes dendrimers as useful nanoscale catalysts. The main advantage of the dendritic catalysts is they can be separated from the reaction mixture by simple solvent precipitation and reused for several times with similar catalytic activity. Importance of catalytically active substances like metal salts or organic molecule like pyrrolidinylmethanol thatare attached either to the core or to the periphery of the dendrimers have been highlighted and their applications in important organic reactions such as Baylis-hillman, Mannich-type, Diels-Alder, Wittig reaction, Michael addition, addition of dialkylzinc to aldehyde, asymmetric epoxide ring opening, asymmetric hydrogenation and asymmetric epoxidation are also presented. Use of dendrimer based salts and chiral compounds in asymmetric syntheses are discussed and the advantages and disadvantages of those catalysts are brought out in this review.