In:
Chemistry – A European Journal, Wiley, Vol. 20, No. 41 ( 2014-10-06), p. 13345-13355
Abstract:
Rh‐containing metallacycles, [(TPA)Rh III (κ 2 ‐( C , N )‐CH 2 CH 2 (NR) 2 ‐]Cl; TPA= N , N , N,N ‐tris(2‐pyridylmethyl)amine have been accessed through treatment of the Rh I ethylene complex, [(TPA)Rh(η 2 ‐ CH 2 CH 2 )]Cl ([ 1 ]Cl) with substituted diazenes. We show this methodology to be tolerant of electron‐deficient azo compounds including azo diesters (RCO 2 NNCO 2 R; R=Et [ 3 ]Cl, R= i Pr [ 4 ]Cl, R= t Bu [ 5 ]Cl, and R=Bn [ 6 ]Cl) and a cyclic azo diamide: 4‐phenyl‐1,2,4‐triazole‐3,5‐dione (PTAD), [ 7 ]Cl. The latter complex features two ortho ‐fused ring systems and constitutes the first 3‐rhoda‐1,2‐diazabicyclo[3.3.0]octane. Preliminary evidence suggests that these complexes result from N–N coordination followed by insertion of ethylene into a [Rh] N bond. In terms of reactivity, [ 3 ]Cl and [ 4 ]Cl successfully undergo ring‐opening using p ‐toluenesulfonic acid, affording the Rh chlorides, [(TPA)Rh III (Cl)(κ 1 ‐( C )‐CH 2 CH 2 (NCO 2 R)(NHCO 2 R)]OTs; [ 13 ]OTs and [ 14 ]OTs. Deprotection of [ 5 ]Cl using trifluoroacetic acid was also found to give an ethyl substituted, end‐on coordinated diazene [(TPA)Rh III (κ 2 ‐( C,N )‐CH 2 CH 2 (NH) 2 ‐] + [ 16 ]Cl, a hitherto unreported motif. Treatment of [ 16 ]Cl with acetyl chloride resulted in the bisacetylated adduct [(TPA)Rh III (κ 2 ‐( C,N )‐CH 2 CH 2 (NAc) 2 ‐] + , [ 17 ]Cl. Treatment of [ 1 ]Cl with AcNNAc did not give the RhN insertion product, but instead the N,O‐chelated complex [(TPA)Rh I ( κ 2 ‐( O,N )‐CH 3 (CO)(NH)(NC(CH 3 )(OCHCH 2 ))]Cl [ 23 ]Cl, presumably through insertion of ethylene into a [Rh] O bond.
Type of Medium:
Online Resource
ISSN:
0947-6539
,
1521-3765
DOI:
10.1002/chem.201403682
Language:
English
Publisher:
Wiley
Publication Date:
2014
detail.hit.zdb_id:
1478547-X
detail.hit.zdb_id:
1231884-X
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