B. Gita

Govindarajan Sundararajan

copolymer

norbornane derivative

article

photochemistry

priority journal

synthesis

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

Synthesis of homo and block copolymers of norbornene with W(CO)6 via photo-initiation

Tetrahedron Letters

Conjugated polymers with ferrocene units as pendants or as end-groups have been systhesised using the classical metathesis polymerisation catalyst W(CO)6 under photo-irradiation. The polymers are characterised by spectroscopic techniques and the redox-behaviour of these complexes have been examined by cyclic voltammetry. © 2002 Elsevier Science B.V. All rights reserved.

Journal of Organometalic Chemistry

Synthesis of conjugated polymers with ferrocene units as pendants or as end-groups

Irradiation of W(CO)6 in CCl4 generates an 'active species' which has the ability to polymerise alkynes and strained cyclic olefins via a metathesis pathway. The precipitate formed after 2 h of irradiation is active for polymerisation. The involvement of metal carbene in the polymerisation of norbornene was proved by in situ 1H-NMR study and by the end-capping reaction. IR studies showed the presence of carbonyl and chlorine ligands around the tungsten centre. © 2000 Elsevier Science S.A.

Journal of Organometallic Chemistry

Studies on the nature of active species in W(CO)6/CCl4/hν system as applied to metathesis polymerisation reactions

Metathesis polymerisation can be effected with many catalysts under a variety of conditions. The system described here, viz., W(CO)6/CBr4/hv, induces polymerisation by in situ generation of the active species and has not been reported in the literature so far. In this paper, optimisation studies of this system, yields obtained with various monomers and characterisation of the active species are discussed. Variation of different parameters such as the ratio of W(CO)6:CBr4, the time of photolysis and the effect of solvents as well as that of the metal carbonyls have been studied. In addition, copolymers of phenylacetylene and norbomene have been synthesised. We have also attempted to characterise the active species responsible for the polymerisation by reaction with acetophenone.

Journal of Molecular Catalysis A: Chemical

W(CO)6/CBr4/hv - A new system for metathesis polymerisation

Substituted phenylacetylenes are polymerized using in situ generated (arene) M(CO)3 complexes as catalysts. The catalytic activity of the complexes is discussed with reference to the metals and arene ligands. A ladder polymer of phenylacetylene formed via cycloaddition mechanism as a possible precursor to linear polyphenylacetylenes, in bulk polymerization conditions, has been isolated and characterized. Some of the properties of the polymers are also described. © 1995.

Journal of Molecular Catalysis. A, Chemical

Metathetical polymerization of substituted phenylacetylenes using in situ generated (arene)M(CO)3 complexes (arene = toluene, o-xylene or mesitylene, M Cr, Mo or W) as catalysts

The results of optical phase conjugation experiments in a degenerate four-wave mixing geometry are reported at 532 nm in a new block copolymer of phenylacetylene and norbornene. The copolymer sample with an equal number of repeating units for the two homopolymers prepared by sequential addition of the monomers gives a third-order susceptibility value which is twice that of the homopolymer of phenylacetylene. © 1995.

Journal	Tetrahedron Letters
ISSN	00404039
Open Access	No