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Title: N‐Heterocyclic Carbene‐Assisted Reversible Migratory Coupling of Aminoborane at Magnesium
Abstract A combined synthetic and theoretical investigation of N‐heterocyclic carbene (NHC) adducts of magnesium amidoboranes is presented, which involves a rare example of reversible migratory insertion within a normal valents‐block element. The reaction of (NHC)Mg(N(SiMe3)2)2(1) and dimethylamine borane yields the tris(amide) adduct (NHC−BN)Mg(NMe2BH3)(N(SiMe3)2) (2; NHC−BN = NHC−BH2NMe2). In addition to Me2N=BH2capture at theNHCC−Mg bond, mechanistic investigations suggest the likelihood of aminoborane migratory insertion from an RMg(NMe2BH2NMe2BH3) intermediate. To elucidate these processes, the carbene complexes (NHC)Mg(NMe2BH3)2(8) and (NHC)Mg(NMe2BH2NMe2BH3)2(9) were synthesized, and a dynamic migration of Me2N=BH2between Mg−N andNHCC−Mg bonds was observed in9. This unusual reversible migratory insertion is presumably induced by dissimilar charge localization in the−{NMe2BH2NMe2BH3} anion, as well as the capacity of NHCs to reversibly capture Me2N=BH2in the presence of Lewis acidic magnesium species.  more » « less
Award ID(s):
2102552 2018870
PAR ID:
10371247
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
61
Issue:
43
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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