Chloro(diethylamino)tris(μ-diethylcarbamato)dizinc(II): an example of the generality of the threefold paddlewheel structure in carbamatozinc chemistry

Abstract

Key indicatorsSingle-crystal X-ray study T = 173 K Mean '(C±C) = 0.003 A Ê Disorder in main residue R factor = 0.023 wR factor = 0.056 Data-to-parameter ratio = 12.6For details of how these key indicators were automatically derived from the article, see

Formation of a Unique Zinc Carbamate by CO2 Fixation: Implications for the Reactivity of Tetra-Azamacrocycle Ligated Zn(II) Complexes

“…26 The common coordination mode for carbamates at zinc centers is µ 2 -bridging, for which several X-ray structures have been reported. [27][28][29][30][31][32][33][34][35] Three of the four nitrogens are coordinated to the zinc(II) center. The carboxyl group of the carbamate is located at the fourth nitrogen, which is positioned between two ethylene bridges.…”

“…Moreover, just one comparable carbamato complex of zinc(II) with monodentate carbamate coordination has been described in the literature until now . The common coordination mode for carbamates at zinc centers is μ 2 -bridging, for which several X-ray structures have been reported. – …”

Recent Advances in the Chemistry of Metal Carbamates

“…Partial ligand substitution along the MCl n /CO 2 /R 2 NH pathway gives access to mixed species such as metal chlorido-carbamates or amino-chlorido-carbamates [ 42 ]. For instance, the reaction of ZnCl 2 with Et 2 NH/CO 2 in THF afforded [Zn 2 (μ-O 2 CNEt 2 ) 3 Cl(Et 2 NH)], displaying a paddlewheel structure with bridging ( B/2 ) carbamato ligands [ 230 ]. A very recent example of partial substitution from a metal chloride is the reaction of TiCl 4 with one equivalent of preformed [TMG][O 2 CNEt 2 ] (TMG = tetramethylguanidine), leading to the trinuclear [TiCl 2 (O 2 CNEt 2 ) 2 ] 3 [ 109 ].…”

Tetrakis(N,N-diethylcarbamato)titanium(IV)

“…The Ti-O bond distances are all similar, ranging between 2.0530 (15) and 2.1087 16Å, while the O-C-O angles of the carbamate ligands range from 115.3 (2) to 116.7 (2)°. These angles are considerably smaller than O-C-O angles in complexes having terminal η 1 or µ 1,3 -bridging carbamato ligands, which tend to be greater than 120°, and they are small even when compared to other bidentate carbamato ligands (Dell′Amico et al, 2003;McCowan et al, 2004). The compressed O-C-O angles in the title compound are attributed in part to the high coordination number about the Ti IV center, which has the effect of forcing the O atoms closer to one another.…”