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The catalytic asymmetric [3+2] cycloaddition of (3-isothiocyanato)oxindoles with azodicarboxylates has been explored in the presence of (DHQD)2PHAL. It affords spirooxindoles having two heterocycles at their C3′-position in excellent yields, with high enantioselectivities, and under mild conditions within 5 min. Moreover, another spirooxindole derived from the reaction of (3-isothiocyanato)oxindole with two molecules of azodicarboxylate could also be formed in excellent yields with the same high enantioselectivities under the standard conditions.

Tell me which you want: catalytic asymmetric [4+2] cycloadditions of β,γ-unsaturated α-ketophosphonates with allenic esters catalyzed by organocatalysts derived from different cinchona alkaloids have been developed, affording phosphonate-substituted functionalized pyran and dihydropyran derivatives in excellent yields with high enantioselectivities under mild conditions. The choice of product is controlled by the hydrogen bonding characteristics of the chosen catalyst.

Phosphorus containing Lewis base catalyzed cascade reactions of isatin-derived oximes with allenic esters afford the corresponding functionalized nitrones. Further Lewis acid catalyzed highly regioselective intramolecular [3+2] cyclizations give the corresponding bridged cycloadducts. Moreover, a combined “one-pot” reaction is also feasible for the above two catalytic reactions.

β-Isocupreidine (β-ICD) catalyzed asymmetric [4 + 2] cycloaddition of β,γ-unsaturated α-ketoesters with allenic esters afforded ester-substituted functionalized dihydropyran derivatives in high yields along with high enantioselectivities under mild conditions.

Lewis base-catalyzed cyclization reactions of allenoates with electron-deficient olefins and imines have been demonstrated by the preparation of biologically active natural products and pharmaceutically interesting substances and have emerged as powerful synthetic tools in the rapid construction of cyclic molecular complexity. In contrast to phosphine-containing Lewis bases, nitrogen-containing Lewis base amines display markedly different reaction profiles; however, this area is not well-developed. Herein we summarize the recent progress in this emerging field and outline the challenges ahead.

Ketophosphonates (I) afford mainly dihydropyran derivatives, whereas ketoesters (V) give predominantly highly functionalized tetrahydropyran derivatives.

In the presence of the quinidine-derived β-isocupreidine as organocatalyst, the products are obtained with good to high e.e.

A series of novel quinidine-derived organocatalysts was synthesized and utilized for the asymmetric substitution of O-Boc-protected Morita–Baylis–Hillman adducts with various carbamates and tosylcarbamates, affording the corresponding products in good to high yields (up to 91 % yield) with moderate to high ee values (up to 96 % ee) under mild conditions.