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In this paper, phosphine-catalyzed [3 + 3] annulation of Morita-Baylis-Hillman carbonates with C, N-cyclic azomethine imines has been achieved. The reaction worked smoothly under mild conditions to afford 4,6,7,11b-tetrahydro-1 H-pyridazino[6,1- a]isoquinoline derivatives in high yields with good to excellent diastereoselectivities. [ABSTRACT FROM AUTHOR]

Enantioselective synthesis of chiral quinazoline-based heterocycles is achieved through a chiral phosphine-catalyzed [3+3] annulation reaction of quinazoline-based 1,3-dipoles with Morita−Baylis−Hillman carbonates. The reaction proceeds smoothly under mild conditions to give various chiral heterocyclic compounds in high yields with excellent diastereoselectivities and enantioselectivities. Further diverse elaborations of the annulation products work well to produce novel tetrahydroquinazoline derivatives. [ABSTRACT FROM AUTHOR]

With the use of a bifunctional chiral phosphine as the catalyst, the asymmetric [3+2] annulation of Morita-Baylis-Hillman carbonates with cyclic 1-azadienes proceeded smoothly under mild conditions to give various enantiomerically enriched cyclopentene derivatives bearing three consecutive tertiary stereocenters and a sulfamate moiety in moderate to excellent yields with moderate to excellent enantioselectivities and excellent diastereoselectivities. [ABSTRACT FROM AUTHOR]

A multifunctional chiral phosphine-catalyzed enantioselective [3+2] annulation of Morita-Baylis-Hillman carbonates with barbiturate-derived alkenes has been achieved under mild conditions, providing a variety of chiral spirobarbiturate-cyclopentenes in moderate to excellent yields with moderate to excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

An efficient method for the phosphine-catalyzed [3+2] cycloaddition reaction of azomethine imines with diphenylsulfonyl alkenes to give dinitrogen-fused bi- or tricyclic heterocyclic compounds in high yields has been described. Moreover, two phenylsulfonyl groups installed on the heterocyclic products could be conveniently removed or transformed to other functional groups, making the reaction more useful. [ABSTRACT FROM AUTHOR]

The asymmetric [3 + 3] cycloaddition of C,N-cyclic azomethine imines with aryl-substituted Morita-Hillman carbonates (II, IV) is developed using a spirocyclic chiral phosphine as the catalyst. [ABSTRACT FROM AUTHOR]

The phosphine-catalyzed [3 + 2] cycloaddition reaction of various azomethine imines with electron-deficient phenylsulfonyl alkenes is described. [ABSTRACT FROM AUTHOR]

Abstract: Using n-PrPPh2 as the nucleophilic catalyst, the [4+2] cycloaddition reaction of the sulfamate-derived cyclic imines with allenoates works efficiently to yield various sulfamate-fused tetrahydropyridines in high yields with excellent diastereoselectivities. Using amino acid-based bifunctional phosphine as chiral catalyst, an asymmetric [4+2] cycloaddition reaction was achieved, giving chiral sulfamate-fused tetrahydropyridines in high yields with good enantiomeric excesses. [Copyright &y& Elsevier]

The article presents chemical reaction for phosphine-catalyzed [4 + 2] cycloaddition of unsaturated pyrazolones with allenoates.

The title reaction affords sulfamate-fused dihydropyrroles (III) and (VI) in moderate to good yields. [ABSTRACT FROM AUTHOR]