Accession Number:

ADA272647

Title:

Rotational Isomers of Mo(VI) Alkylidene Complexes and Cis/Trans Polymer Structure: Investigations in Ring-Opening Metathesis Polymerization

Descriptive Note:

Technical rept.,

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

1993-10-20

Pagination or Media Count:

49.0

Abstract:

In the last few years well-defined metathesis catalysts of the general type MNRCHROR2 MMo or W have proven useful in a variety of olefin metathesis studies, in part because the activity of catalysts can be varied systematically by altering the electron-withdrawing ability of the alkoxides. Complexes containing t-butoxides OCMe3 and OCMeCf32 in particular , an arylimido ligand often NAr, where Ar 2,6-i-Pr2C6H3, and molybdenum have been the most versatile. In the area of ring-opening metathesis polymerization ROMPmolybdenum complexes have been employed most often to prepare polymers from a variety of norbornenes and norbornadienes. Molybdenum complexes appear to tolerate a wide range of functionalities, are stable and active in a variety of solvents,and have been shown to produce polymers that are virtually all trans and highly tactic or all cis with a tactic bias of approx. 75. Alkylidene rotational isomers or rotamers eq 1 are found for many high-oxidation state alkylidene complexes

Subject Categories:

  • Inorganic Chemistry
  • Physical Chemistry
  • Polymer Chemistry
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE