T. Balasubramanian

Bio: T. Balasubramanian is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Ether & Claisen rearrangement. The author has an hindex of 3, co-authored 3 publications receiving 27 citations.

Radical Cyclisation of o-Haloaryl Allenylmethyl Ethers and Amines: Synthesis of 3-Ethenyl-2,3-dihydrobenzofurans and 3-Ethenyl-2,3-dihydroindoles

Abstract: o-Haloaryl allenylmethyl ethers and amines upon treatment with n-Bu3SnH and AIBN in refluxing benzene, underwent a 5-exo-trig free radical cyclisation to give the respective 3-ethenyl-2,3-dihydrobenzofurans and 3-ethenyl-2,3-dihydroindoles in good yields.

Synthesis of 3,4-Disubstituted 2H-Benzopyrans Through C-C Bond Formation via Electrophilic Cyclization

Abstract: The electrophilic cyclization of substituted propargylic aryl ethers by I2, ICl, and PhSeBr produces 3,4-disubstituted 2H-benzopyrans in excellent yields. This methodology results in vinylic halides or selenides under mild reaction conditions and tolerates a variety of functional groups, including methoxy, alcohol, aldehyde, and nitro groups.

Mechanistic Aspects and Synthetic Applications of Radical Additions to Allenes.

Abstract: More than 50 years have passed since Haszeldine reported the first addition of a trifluoromethyl radical to an allene; in the intervening years, both the chemistry of allenes and the reactivity of single-electron species have become topics of intense interest. In this Review, we provide an overview of the fundamentals of radical additions to allenes and highlight the emergence of theoretical and experimental evidence that reveals unique reactivity patterns for radical additions to allenes as compared with other unsaturated compounds. Factors capable of exerting control over the chemo-, regio-, and stereoselectivities of the attack of carbon- and heteroatom-based radicals at each of the three potential reactive sites in an allene substrate are described. These include reaction conditions, the nature of the attacking radical, the substitution pattern of the allene, and the length of the linker between the radical center and the proximal allene carbon in the substrate. Cycloaddition reactions between allenes and partners containing π-bonds, which are likely to proceed through radical pathways, are presented to highlight their ability to rapidly access complex polycyclic scaffolds. Finally, the synthetic utility of the products arising from these chemistries is described, including their applications to the construction of complex molecules.

Tandem transformations of N-alkyl-N-allenylmethylanilines to N-alkyl-2-ethenylindoles

Abstract: Treatment of N-alkyl-N-allenylmethylanilines with magnesium monoperoxyphthalate in methanol–water underwent tandem transformations to furnish N-alkyl-2-ethenylindoles in good yield.