Ramamurthy Nagarajan

Department Of Chemical Engineering

Kalapattukuppuswamy Kuppuswamy B. Balasubramanian

K. Virupaksha Reddy

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

A novel mercuric ion catalysed reaction of 1,6‐diaryloxy‐2,4‐hexadiynes to 4,4′‐bichromenes

Tetrahedron Letters

Axially chiral molecules have established undisputed importance in both medicinal chemistry and enantiomeric catalysis. The size, shape and hybridization of the substituent adjacent to the rotational axis greatly dictate atropisomerism. Herein, we examined the tropoisomeric behavior of 4,4′-bichromenes and 4,4′-bithiochromenes derivatives that were synthesized by a nickel catalyzed reductive homocoupling strategy. The as-synthesized 3,3′-disubstituted 4,4′-bichromenes displayed atropisomerism, as evidenced by chiral stationary phase HPLC, electronic circular dichroism and single crystal XRD studies. Insights into the torsional barrier about the internuclear axis in 4,4′-bichromenes were gained both experimentally and theoretically (DFT studies). The lower activation energy barrier (Ea) of approximately 12 kcal mol-1 as compared to that of fully aromatic 1,1′-binapthyl explains the conformationally unstable nature of 3,3′-unsubstituted 4,4′-bichromenes at room temperature. © the Partner Organisations.

Fulltext

Organic Chemistry Frontiers

Nickel catalyzed synthesis of 4,4′-bichromenes/4,4′-bithiochromenes and their Atropisomerism

The thermal rearrangement of 2,4-di(N-aryl)amino-1,3,5-triazin-6yl-prop-2-ynyl ethers 1 yield a mixture of 6-methyleneimidazo(1,2-a)-1,3,5-triazine-4-one 6 and 6-methylimidazo(1,2-a)-1,3,5-triazine-4-one 7, whereas under the influence of mercuric trifluroacetate the ethers 1 yield only 6, at room temperature. Mechanisms invoking [3,3] sigmatropic rearrangement of ethers 1 were proposed to account for the product formation. © 1985.

Tetrahedron

Studies in claisen rearrangement - novel thermal and mercuric trifluroacetate induced transformations of 2,4-di(N-aryl)amino-1,3,5-triazin-6yl-prop-2-y

13C NMR data for 1,6‐bis derivatives of hexa‐2,4‐diynes are reported. Introduction of a sulphone or sulphoxide moiety at C‐1, C‐6 in place of sulphide, ether or amino groups caused a 6–7 ppm upfield shift (β effect) for the C‐2, C‐5 carbons and a 3–4 ppm downfield shift (y effect) for the C‐3, C‐4 carbons. Copyright © 1988 John Wiley &amp; Sons, Ltd.

Magnetic Resonance in Chemistry

Carbonâ€13 NMR spectra of 1,6â€bis derivatives of hexaâ€2,4â€diynes

Migration und Avantgarde

ChemInform

ChemInform Abstract: Stereochemistry and Fate of Hydrogen Atoms in the Diol-Dehydratase-Catalyzed Dehydration of meso-Butane-2,3-diol.

Journal of the American Chemical Society

Thallium in organic synthesis. XXXIV. Oxidations of acetylenes with thallium(III) nitrate (TTN)

Journal of Synthetic Organic Chemistry, Japan

2-Isopropenyl-4, 5-dimethyloxazole

Horizons of Bioenergetics

ENERGY SOURCES FOR TUMOR GROWTH**The new data presented here from our laboratory are taken from a dissertation by B. Nagarajan, Vanderbilt University, 1970.

A novel mercuric ion catalysed reaction of 1,6-diaryloxy-2,4-hexadiynes to 4,4'-bichromenes

Journal	Tetrahedron Letters
ISSN	00404039
Open Access	No