Record Details

From large 12-membered macrometallacycles to ionic (NHC)(2)M(+)Cl(-) type complexes of gold and silver by modulation of the N-substituent of amido-functionalized N-heterocyclic carbene (NHC) Ligands

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title From large 12-membered macrometallacycles to ionic (NHC)(2)M(+)Cl(-) type complexes of gold and silver by modulation of the N-substituent of amido-functionalized N-heterocyclic carbene (NHC) Ligands
 
Creator SAMANTARAY, MK
PANG, K
SHAIKH, MM
GHOSH, P
 
Subject ring-opening polymerization
ab-initio pseudopotentials
luminescent silver(i)
structural diversity
transition-elements
tetranuclear silver
l-lactide
dinuclear
metal
catalysis
 
Description A series of structurally diverse gold and silver complexes extending from ionic (NHC)(2)M(+)Cl(-) (M = Au, Ag) type complexes to large 12-membered macrometallacycles have been prepared by the appropriate modification of the N-substituent of amido-functionalized N-heterocyclic carbenes. Specifically, the ionic, [1-(R)-3-{N-(t-butylacetamido)imidazol-2-ylidene}](2)M(+)Cl(-), (R = t-Bu, i-Pr; M = Au, Ag; 1b, 1c, 2b, 2c) complexes, were obtained in case of the N-t-butyl substituent of the amido-functionalized sidearm while 12-membered macrometallacycles, [1-(R)-3-{N-(2,6-dii-propylphenylacetamido)imidazol-2-ylidene}](2)M(2), (R = t-Bu, i-Pr; M = Au, Ag; 3b, 3c, 4b, 4c) were obtained in case of the 2,6-dii-propylphenyl N-substituent. These structurally diverse complexes of gold and silver were, however, prepared employing a common synthetic pathway involving the reactions of the imidazolium chloride salts (1a, 2a, 3a, 4a) with Ag(2)O to give the silver complexes (1b, 2b, 3b, 4b) and which, when treated with (SMe(2))AuCl, gave the gold complexes (1c, 2c, 3c, 4c). Detailed density functional theory studies of 1b, 1c, 2b, 2c, 3b, 3c, 4b, and 4c were carried out to gain insight about the structure, bonding, and the electronic properties of these complexes. The NHC-metal interaction in the ionic 1b,,1c, 2b, and 2c complexes is primarily composed of the interaction of the carbene lone pair with the empty p orbital of the metal (5p for Ag and 6p for Au) while the same in the macrometallacyclic 3b, 3c, 4b, and 4c complexes consisted of the interaction of the carbene lone pair with the empty s orbital of the metal (5s for Ag and 6s for Au). The observation of a low energy emission in about the 580-650 nm region has been tentatively assigned to originate from the presence of weak metallophilic interaction in these macrometallacyclic 3b, 3c, 4b, and 4c complexes.
 
Publisher AMER CHEMICAL SOC
 
Date 2011-07-14T06:02:00Z
2011-12-26T12:48:13Z
2011-12-27T05:46:43Z
2011-07-14T06:02:00Z
2011-12-26T12:48:13Z
2011-12-27T05:46:43Z
2008
 
Type Article
 
Identifier INORGANIC CHEMISTRY, 47(10), 4153-4165
0020-1669
http://dx.doi.org/10.1021/ic702186g
http://dspace.library.iitb.ac.in/xmlui/handle/10054/3873
http://hdl.handle.net/10054/3873
 
Language en