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  • Reductive cleavage of N , N ′-di- tert -butylcarbodiimide generates tert -butylcyanamide ligands, (Me 3 CNCN) − , that bind potassium both end-on and side-on in the same single crystal
Title: Reductive cleavage of N , N ′-di- tert -butylcarbodiimide generates tert -butylcyanamide ligands, (Me 3 CNCN) − , that bind potassium both end-on and side-on in the same single crystal
N , N ′-Di- tert -butylcarbodiimide, Me 3 CN=C=NCMe 3 , undergoes reductive cleavage in the presence of the Gd II complex, [K(18-crown-6) 2 ][Gd II (N R 2 ) 3 ] ( R = SiMe 3 ), to form a new type of ligand, the tert -butylcyanamide anion, (Me 3 CNCN) − . This new ligand can bind metals with one or two donor atoms as demonstrated by the isolation of a single crystal containing potassium salts of both end-on and side-on bound tert -butylcyanamide anions, (Me 3 CNCN) − . The crystal contains [K(18-crown-6)(H 2 O)][NCNCMe 3 - kN ], in which one ( t BuNCN) − anion is coordinated end-on to potassium ligated by 18-crown-6 and water, as well as [K(18-crown-6)][η 2 -NCNCMe 3 ], in which an 18-crown-6 potassium is coordinated side-on to the terminal N—C linkage. This single crystal also contains one equivalent of 1,3-di- tert -butyl urea, (C 9 H 20 N 2 O), which is involved in hydrogen bonding that may stabilize the whole assembly, namely, aqua( tert -butylcyanamidato)(1,4,7,10,13,16-hexaoxacyclooctadecane)potassium(I)–( tert -butylcyanamidato)(1,4,7,10,13,16-hexaoxacyclooctadecane)potassium(I)– N , N ′-di- tert -butylcarbodiimide (1/1/1) [K(C 5 H 9 N 2 )(C 12 H 24 O 6 )]·[K(C 5 H 9 N 2 )(C 12 H 24 O 6 )(H 2 O)]·C 9 H 20 N 2 .  more » « less
Award ID(s):
1855328
NSF-PAR ID:
10232084
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Acta Crystallographica Section E Crystallographic Communications
Volume:
76
Issue:
7
ISSN:
2056-9890
Page Range / eLocation ID:
1047 to 1050
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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