title: Syntheses of arabinose-derived pyrrolidine catalysts and their applications in intramolecular Diels-Alder reactions.
abstract: Six chiral hydroxylated pyrrolidine catalysts were synthesized from commercially available D-arabinose in seven steps. Various aromatic substituents α to the amine can be introduced readily by a Grignard reaction, which enables facile optimization of the catalyst performance. The stereoselectivities of these catalysts have been assessed by comparing with those of MacMillan's imidazolidinone in a known intramolecular Diels-Alder (IMDA) reaction of a triene. Two additional IMDA reactions of symmetrical dienals with concomitant desymmetrisation further established the potential use of these novel amine catalysts. These pyrrolidines are valuable catalysts for other synthetic transformations.
authors.affiliation: Department of Chemistry and Center of Novel Functional Molecules, The Chinese University of Hong Kong, Shatin, Hong Kong, China. tonyshing@cuhk.edu.hk.
authors.forename: Tony K M
authors.initials: TK
authors.lastname: Shing
authors.forename: Kwun W
authors.initials: KW
authors.lastname: Wu
authors.forename: Ho T
authors.initials: HT
authors.lastname: Wu
authors.forename: Qicai
authors.initials: Q
authors.lastname: Xiao