The chemistry of the hydrazido(1–)-ligand. Preparations and crystal structures of [Mo(NHNHCO₂Me)(NNCO₂Me)(S₂CNMe₂)₂], [Mo(NHNMePh)(NNMePh)(S₂CNMe₂)₂]BPh₄, and [ReCl₂(NHNHCOPh)(NNHCOPh)(PPh₃)₂]. Mechanism of formation of substituted hydrazines from [Mo(NNRPh)₂(S₂CNMe₂)₂](R = Me or Ph)

Abstract

265ChemInform Abstract Bis(hydrazido(2-)) complexes such as Mo(N2R1Ph)2(S2CNR22)2 (R1: Me, Ph; R2: Me, Et) react with an excess of HX in methanol (generated in situ by addition of Me3SiX) to give the corresponding hydrazine and the dichloro complexes MoCl2(N2R1Ph)(S2CNR22)2. However, reaction with 1 equiv. HX gives monohydrazido(1-) derivatives such as (I), isolated as tetraphenylborate salts. Kinetic studies of the intermediacy of such a species in the hydrazine-forming reaction are reported and discussed. The Re complex (V) is obtained by reaction of the hydrazido(2-) complex (III) with benzoylhydrazine (IV). Molecular and crystal structures of the title compounds (I) (space group P21/n, Z=4), (II) (C2/c, Z = 8), and (V) (P1, Z=2) are determined by X-ray analysis and are discussed.

Mononuclear Five- and Six-Coordinate Iron Hydrazido and Hydrazine Species

“…Schrock noted a similar discrepancy in the hydrazido NH/NH 2 resonances of WCp*Me 3 (η 2 -N 2 H 3 ) + ( N H: 241.26 ppm, N H 2 : 30.97 ppm), 6e which has been attributed to formation of a π bond between the hydrazido NH nitrogen and the W center (structural data corroborates this assignment). While such a bonding scenario is typical for M(η 2 -N 2 R 3 ) species of the early-to-mid transition metals, 4a,5a,5b,5e,6e,7c the high d-electron counts for late transition metals usually preclude this coordination mode; Huttner’s d 7 L 3 Co(η 2 -N 2 R 3 ) + species is an exception. 6i …”

“…4 In light of this, most studies on M(N 2 R 3 ) species feature substituted hydrazido ligands, 5 and a comparatively small subset feature the parent hydrazido (N 2 H 3 − ) functionality. 6 This relative scarcity may also be due in part to the different inherent stabilities of M(N 2 R x ) and M(N 2 H x ) species.…”

Copolymerization of Isoprene and Nonconjugated α,ω‐Dienes by Half‐Sandwich Scandium Catalysts with and without a Coordinative Side Arm

“…(3), [6f] C 5 Me 4 NHCMeI (4 a), [12] [13] were synthesized as described previously. The deuterated solvents [D 6 ]benzene (99.6 atom % D), [D 8 ]THF (99.6 atom % D), CDCl 3 (99.8 atom % D), and 1,1,2,2-[D 2 ]tetrachloroethane (99.6 atom % D) were obtained from Cambridge Isotope.…”

“…Because no NMR spectroscopic information on the HD-IP copolymers could be found in the literature, we then carried out a detailed characterization of our copolymer products by means of 1 H, 13 C, DEPT-13 C, HSQC (heteronuclear singular quantum correlation), H2BC (heteronuclear twobond correlation), and HMBC (heteronuclear multiple-bond correlation) NMR spectroscopic analyses (see the Supporting Information) to establish the co-monomer incorporation and distribution in the copolymer chains. Relatively weak signals were carefully assigned by comparison of the spectral data with those of copolymers with different monomer contents and those of related polymers reported previously.…”

Electrochemical Cleavage of NdN Bonds at a Mo2(μ-SMe)3 Site Relevant to the Biological Reduction of Dinitrogen at a Bimetallic Sulfur Centre

“…[46,49] The NÀN bond might be cleaved as shown in Scheme 7, step C. However, several examples in the literature show that protonation of hydrazido(1 À ) ligands does not necessarily lead to NÀN bond cleavage. The protonated ligand can be released as hydrazine [45, 46, 49±52] (protonated or not) or kept in the metal coordination sphere as an h 2 hydrazine ligand.…”