An account of the synthetic utility of masked o-benzoquinones is provided. The inter- and intramolecular Diels-Alder reactions of in situ generated masked o-benzoquinones produced cycloadducts in excellent selectivities. New synthetic methodologies have been developed for the synthesis of highly substituted ring systems including bicyclo[2.2.2]octenones, oxatricycles, triquinanes, polysubstituted cyclohexanes, and bicyclo[4.2.2]decenones with complete stereocontrol from easily accessible 2-methoxyphenols via the Diels-Alder reaction of masked o-benzoquinones. Other reactions of adducts derived from masked o-benzoquinones are also described. The efficacy of our methodology is demonstrated by several examples of the total synthesis of natural products.

A highly efficient, elegant and simple procedure with exceptionally mild conditions has been proposed for the synthesis of b-amino-acrylate derivatives and an array of biologically and pharmaceutically active benzoheterocycles. The protocol offers a valuable alternative to known methods and will find applications in the field of green synthesis. The regio-and stereo-chemistry of the products were established by IR, NMR and single crystal X-ray analysis.

A novel, efficient and unprecedented green protocol for the formation of C-S bond has been developed under metal-free conditions. This protocol involves the synthesis of aryl sulfides through the cross-dehydrogenative coupling of readily available aryl thiols with electron-rich species under 10 solvent-free conditions and the corresponding aryl sulfides are obtained in high to quantitative yields. A catalytic amount of inexpensive and non-toxic iodine drives the reaction and no exclusion of air and expensive ligands are required.

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Highly reactive o-benzoquinone monoimines were chemically generated and successfully trapped with electron-rich olefins that led to the synthesis of hitherto unknown 1,4-benzoxazine derivatives. This unprecedented transformation was achieved by the oxidation of o-aminophenols bearing appropriate functionality on the arene residue with less expensive hypervalent iodine reagent in the presence of vinylic ethers or thioethers.