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Title: An η 3 ‐Bound Allyl Ligand on Magnesium in a Mechanochemically Generated Mg/K Allyl Complex
Abstract

Milling two equivalents of K[1,3‐(SiMe3)2C3H3] (=K[A′]) with MgX2(X=Cl, Br) produces the allyl complex [K2MgA′4] (1). Crystals grown from toluene are of the solvated species [((η6‐tol)K)2MgA′4] ([1⋅2(tol)]), a trimetallic monomer with both bridging and terminal (η1) allyl ligands. When recrystallized from hexanes, the unsolvated1forms a 2D coordination polymer, in which the Mg is surrounded by three allyl ligands. The C−C bond lengths differ by only 0.028 Å, indicating virtually complete electron delocalization. This is an unprecedented coordination mode for an allyl ligand bound to Mg. DFT calculations indicate that in isolation, an η3‐allyl configuration on Mg is energetically preferred over the η1‐ (σ‐bonded) arrangement, but the Mg must be in a low coordination environment for it to be experimentally realized. Methyl methacrylate is effectively polymerized by1, with activities that are comparable to K[A′] and greater than the homometallic magnesium complex [{MgA′2}2].

 
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Award ID(s):
1665327
NSF-PAR ID:
10142746
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
59
Issue:
24
ISSN:
1433-7851
Page Range / eLocation ID:
p. 9542-9548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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