In:
Chemistry – A European Journal, Wiley, Vol. 22, No. 1 ( 2016-01-04), p. 310-322
Abstract:
The coordination chemistry of the 1,2‐BN‐cyclohexanes 2,2‐R 2 ‐1,2‐B,N‐C 4 H 10 (R 2 =HH, MeH, Me 2 ) with Ir and Rh metal fragments has been studied. This led to the solution (NMR spectroscopy) and solid‐state (X‐ray diffraction) characterization of [Ir(PCy 3 ) 2 (H) 2 (η 2 η 2 ‐H 2 BNR 2 C 4 H 8 )][BAr F 4 ] (NR 2 =NH 2 , NMeH) and [Rh( i Pr 2 PCH 2 CH 2 CH 2 P i Pr 2 )(η 2 η 2 ‐H 2 BNR 2 C 4 H 8 )][BAr F 4 ] (NR 2 =NH 2 , NMeH, NMe 2 ). For NR 2 =NH 2 subsequent metal‐promoted, dehydrocoupling shows the eventual formation of the cyclic tricyclic borazine [BNC 4 H 8 ] 3 , via amino‐borane and, tentatively characterized using DFT/GIAO chemical shift calculations, cycloborazane intermediates. For NR 2 =NMeH the final product is the cyclic amino‐borane HBNMeC 4 H 8 . The mechanism of dehydrogenation of 2,2‐H,Me‐1,2‐B,N‐C 4 H 10 using the {Rh( i Pr 2 PCH 2 CH 2 CH 2 P i Pr 2 )} + catalyst has been probed. Catalytic experiments indicate the rapid formation of a dimeric species, [Rh 2 ( i Pr 2 PCH 2 CH 2 CH 2 P i Pr 2 ) 2 H 5 ][BAr F 4 ]. Using the initial rate method starting from this dimer, a first‐order relationship to [amine‐borane] , but half‐order to [Rh] is established, which is suggested to be due to a rapid dimer–monomer equilibrium operating.
Type of Medium:
Online Resource
ISSN:
0947-6539
,
1521-3765
DOI:
10.1002/chem.201502986
Language:
English
Publisher:
Wiley
Publication Date:
2016
detail.hit.zdb_id:
1478547-X
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