Chemoselective Construction of Polycyclic Heterocycles Containing a [6-6-5] or [7-6-5] Tricyclic Core Skeleton from a 2-Isocyanophenyl Propargylic Ester.

Functionalized isocyanide chemistry represents an important research area in organic synthesis. A structurally unique 2-isocyanophenyl propargylic ester has been designed to incorporate the reactivity of isocyanide and propargylic ester functionalities. Thus, the reaction of 2-isocyanophenyl propargylic ester and 2-aminoaromatic aldimine facilitates the synthesis of a wide range of polycyclic benzo[b] indolo [3,2-h][1,6] naphthyridine derivatives.

Diastereoselective Synthesis of Tetracyclic Tetrahydroquinoline Derivative Enabled by Multicomponent Reaction of Isocyanide, Allenoate, and 2-Aminochalcone.

We report here a multicomponent protocol to assemble several polycyclic dihydropyran-fused tetrahydroquinoline structures with excellent diastereoselectivity. This procedure employs simple feedstocks to accomplish a series of diverse structures, which is difficult to attain by traditional sequences.

Phosphine-mediated sequential annulations of allenyl ketone and isocyanide: a bicyclization strategy to access a furan-fused eight-membered ring and a spirocycle.

Phosphine-mediated cascade annulations of allenyl ketone and isocyanide have been disclosed. Two molecular allenyl ketones work as different four-carbon synthons to form two rings, respectively, and thus enables the efficient synthesis of a furan-fused eight-membered ring and a spirocycle.

Cascade cyclization and acyl migration of propargylic esters with isocyanides: rapid access to substituted furans.

A novel rearrangement of ester-activated propargylic acetate with isocyanide has been disclosed. This protocol enables a quick synthesis of polysubstituted furan derivatives. The reaction outcome also reveals that the ester group is employed for the construction of a furan ring and an acyl migration is observed.