Domino Aza-Michael-ih-Diels-Alder Reaction to Various 3-Vinyl-1,2,4-triazines: Access to Polysubstituted Tetrahydro-1,6-naphthyridines.

A straightforward domino aza-Michael-inverse-electron-demand-hetero-Diels-Alder/retro-Diels-Alder reaction between primary and secondary propargylamine derivatives and 3-vinyl-1,2,4-triazines is developed highlighting not only the uniqueness of this dual-heterocyclic platform but also a novel and unprecedented path to polysubstituted tetrahydro-1,6-naphthyridine scaffolds.

A core switching strategy to pyrrolo[2,3-b]quinolines and diazocino[1,2-a]indolinones.

Two novel core-switching rearrangements to natural product-like privileged scaffolds that proceed in up to 99% yield have been developed. The deviation away from planarity of the central N-acyl urea carbonyl, caused by the structure of the medium-sized ring, dictates the exclusive reaction outcome. Proposed mechanisms and products for the reaction pathways are supported by small molecule X-ray crystallography and an isolated intermediate.

Sequential Michael Addition and Enamine-Promoted Inverse Electron Demanding Diels-Alder Reaction upon 3-Vinyl-1,2,4-triazine Platforms.

An original one-pot Michael addition-ihDA/rDA sequence was achieved from 3-vinyl-1,2,4-triazine platforms used as unprecedented Michael acceptors. This sequence provides a novel access to functionalized [2,3]-fused pyridine derivatives via a unique enamine promoted intramolecular ihDA reaction of 1,2,4-triazine intermediates.

Asymmetric catalytic oxidative cleavage of polycyclic systems: the synthesis of atropisomeric diazonanes and diazecanes.

Oxidative cleavage of internal double bonds in polycyclic systems can give access to compounds containing medium- to large-sized rings. In this example, the nine- and ten-membered ring containing compounds that resulted from the mCPBA-mediated (mCPBA=meta-chloroperoxybenzoic acid) oxidative cleavage reaction were shown to exhibit atropisomerism. The reaction of the polycyclic system with catalytic amounts of ruthenium tetraoxide followed by diol cleavage achieved the same synthetic goal.

A new total synthesis of porritoxin.

A concise and efficient total synthesis of the phytotoxin porritoxin is described. The key step of the synthesis is based upon a Parham cyclization methodology which enables the creation of the lactam unit embedded in the title compound framework with the concomitant formation of the tethered hydroxyakyl chain.