Jaya Kishore Vandavasi

An Iron‐Catalyzed Cascade Approach to Benzo[b]carbazole Synthesis Followed by 1,4‐Sulfonyl Migration

A simple and straightforward approach was developed to construct 5H-benzo[b]carbazole derivatives by iron catalysis in a cascade sequence. The notable features of this work include an atom-economical cascade sequence, unprecedented 1,4-sulfonyl migration, tolerance of a variety of functional groups, good yields, and an economical catalytic system.

A convenient method to construct (Z)-oxazines via 6-exo-dig iodocyclization and synthesis of indolin-3-one

An efficient regio-, stereo- and chemo-specific synthesis of 1,3-benzoxazines via 6-exo-dig cyclization to afford the Z-isomer is reported. The structure and connectivity were confirmed unambiguously on the basis of (1)H NMR, NOESY, and ORTEP. Furthermore, DFT studies revealed that the Z-isomer was more stable than the E-isomer. Iodine substituted 1,3-benzoxazines were very useful precursors for cross coupling reactions. Suzuki reaction was carried out successfully and the resulting product was transformed to 1-(4-nitrobenzoyl)-2,2-diphenylindolin-3-one in the presence of a Lewis acid.

A new approach for fused isoindolines via hexadehydro-Diels–Alder reaction (HDDA) by Fe(0) catalysis

A simple method has been developed for the synthesis of fused isoindolines via a cascade HDDA approach catalyzed by Fe2(CO)9. In this work, a 1,3-diyne was involved in a [4 + 2] cycloisomerization with a diynophile to give an aryne intermediate, which was subsequently trapped with –OH nucleophile to beget the fused isoindolines in high yields.

Synthesis of fused triazolo[4,5-d]quinoline/chromene/thiochromene derivatives via palladium catalysis mediated by tetrabutylammonium iodide

An expedient approach for the synthesis of various fused triazoles with varying functionality has been developed successfully via palladium catalysis in ligand free conditions. It was found that the additive TBAI greatly facilitates this palladium catalyzed cyclization to achieve the previously inaccessible fused triazolo[4,5-d]quinoline/chromene/thiochromene derivatives. This method provides a fast and simple access to obtain the fused triazoles in good to excellent yields. The synthesized compounds were screened with different cancer cell lines and the results has shown that compound 2a and 2f acts as inhibitors against specific non-small cell lung cancer cell line.

Comparative study of ring-opening polymerization of L-lactide and ε-caprolactone using zirconium hexadentate bis(aminophenolate) complexes as catalysts

A series of zirconium bis(aminophenolate) complexes as catalysts for the ring opening polymerization of L-lactide (LA) and e-caprolactone (CL) were investigated. Ligands bearing various chelating groups have a profound influence on the catalysis results. Among them, the thiophen-2-yl methyl group showed the greatest activity while the pyridine-2-yl methyl group showed the worst performance with regard to the rate of CL polymerization. However, the trend was reversed for the rate of LA polymerization. The kinetic results indicated a first-order dependency on [CL] and [LA]. However, the order of the catalyst concentration was different. Polymerization proceeded with second-order dependence on [LOMeZr(OBn)2] for CL but with first-order dependence on [LOMeZr(OBn)2] for LA.

Copper-catalyzed one-pot process to construct triazole-linked urea derivatives

ABSTRACT A new one-pot synthetic methodology has been developed to construct the triazole-linked urea derivatives. In the same step, triazole forms from azide and alkyne via click reaction and urea forms from addition reaction of amines and isocyanates. The notable features of this work include wide substrate scope, atom economy, environmental friendliness, and easily accessible starting materials. The preliminary biological screening of synthesized compounds show promising cytotoxic activity in basal cell carcinoma (BCC) cell lines. GRAPHICAL ABSTRACT