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  • Metallacyclobuta‐(2,3)‐diene: A Bidentate Ligand for Stream‐line Synthesis of First Row Transition Metal Catalysts for Cyclic Polymerization of Phenylacetylene
Title: Metallacyclobuta‐(2,3)‐diene: A Bidentate Ligand for Stream‐line Synthesis of First Row Transition Metal Catalysts for Cyclic Polymerization of Phenylacetylene
Abstract Described here is a direct entry to two examples of 3d transition metal catalysts that are active for the cyclic polymerization of phenylacetylene, namely, [(BDI)M{κ2‐C,C‐(Me3SiC3SiMe3)}] (2‐M) (BDI=[ArNC(CH3)]2CH−, Ar=2,6‐iPr2C6H3;M=Ti, V). Catalysts are prepared in one step by the treatment of [(BDI)MCl2] (1‐M,M=Ti,V) with 1,3‐dilithioallene [Li2(Me3SiC3SiMe3)]. Complexes2‐Mhave been spectroscopically and structurally characterized and the polymers that are catalytically formed from phenylacetylene were verified to have a cyclic topology based on a combination of size‐exclusion chromatography (SEC) and intrinsic viscosity studies. Two‐electron oxidation of2‐Vwith nitrous oxide (N2O) cleanly yields a [VV] alkylidene‐alkynyl oxo complex [(BDI)V(=O){κ1‐C‐(=C(SiMe3)CC(SiMe3))}] (3), which lends support for how this scaffold in2‐Mmight be operating in the polymerization of the terminal alkyne. This work demonstrates how alkylidynes can be circumvented using 1,3‐dianionic allene as a segue into M−C multiple bonds.  more » « less
Award ID(s):
1908587
PAR ID:
10537785
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Corporate Creator(s):
Editor(s):
Not, available
Publisher / Repository:
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
Date Published:
Journal Name:
Angewandte Chemie International Edition
Edition / Version:
1
Volume:
63
Issue:
8
ISSN:
1433-7851
Page Range / eLocation ID:
e202318956
Subject(s) / Keyword(s):
Alkylidene Alkylidyne Cyclic Polymer Deprotiometallacyclobutadiene Polymerization
Format(s):
Medium: X Size: 835KB Other: pdf
Size(s):
835KB
Sponsoring Org:
National Science Foundation
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