ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The ring-opening metathesis polymerization of 5-endo-methoxycarbonyl (1), 5-exo-methoxy-carbonyl (2), 5,6-endo,endo-bis(methoxycarbonyl) (3), 5,6-exo,exo-bis(methoxycarbonyl) (4) and 5,6-endo,exo-bis(methoxycarbonyl) (5) derivatives of norbornene, initiated by the tungsten cyclopentylidene complex , have been followed by 1H NMR in situ at 290 - 320 K. The initial metal-carbene adduct P1 is usually distinguishable from the subsequent adducts Pn(n 〉 1). Initiation is generally faster than or as fast as propagation. The propagation rate constants for the monosubstituted derivatives 1 and 2 are two to four times greater than those for the 5,6-disubstituted derivatives 3-5. Arrhenius parameters were determined for the propagation reactions of 1 and 3.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1992.021930713
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