Metallathiirenes. 3.¹ Thiocarbamoyl and Alkoxythiocarbonyl Complexes of Molybdenum(II) and Tungsten(II)

Abstract

Synthetic routes to thiocarbamoyl (thiocarboxamide) complexes of divalent molybdenum and tungsten are reported: The reaction of fac-[Mo(CO) 3 (NCMe) 3 ] with N,N-dimethyl thiocarbamoyl chloride (Me 2 NC(dS)Cl) at low temperature provides a thermally labile intermediate (1) presumed on the basis of subsequent transformations to be [Mo(η 2 -SCNMe 2 )-Cl(CO) 3 (NCMe)]. Reactions of 1 with K[HB(pz) 3 ] (pz ) pyrazol-1-yl), NaC 5 H 5 , bipy, or tmeda provide the complexes [Mo(η 2 -SCNMe 2 )(CO) 2 {HB(pz 4), and [Mo(η 2 -SCNMe 2 )Cl(CO) 2 (tmeda)] (5), respectively. The complex cis,cis,trans-[Mo(η 2 -SCNMe 2 )Cl(CO) 2 (PPh 3 ) 2 ] (6) results from the oxidative addition of Me 2 NC(dS)Cl to [Mo(NCMe) 2 (CO) 2 (PPh 3 ) 2 ] and is one of two isomers obtained from the reaction of 1 with PPh 3 . The complex 2 may also be obtained from reaction of (i) K[Mo(CO) 3 {HB(pz) 3 }] with Me 2 NC(dS)Cl; (ii) [Mo(CO) 3 (η 6 -C 7 H 8 )] with Me 2 NC(dS)Cl and K[HB(pz) 3 ]; and (iii) K[HB(pz) 3 ] with either 5 or 6. Sequential treatment of either [Mo(CO) 3 -Attempts to prepare a mononuclear thiocarbamoyl complex by addition of elemental sulfur or propene episulfide to the aminomethylidyne complex [Mo(tCN i Pr 2 )(CO) 2 {HB(pz) 3 }] (8) were unsuccessful; however addition of [Fe 2 (CO) 9 ] to 8 provided the thermally unstable complex [MoFe(µ-CN i Pr 2 )(CO) 5 {HB(pz) 3 }] (9), which reacts with sulfur to provide the heterobimetallic bridging thiocarbamoyl complex [MoFe(µ-SCN i Pr 2 )(CO) 5 {HB(pz) 3 }] (10). Treating fac-[W(CO) 3 (NCMe) 3 ] sequentially with Me 2 NC(dS)Cl and K[HB(pz) 3 ] provided [W(η 2 -SCNMe 2 )(CO) 2 {HB(pz) 3 }] (11); however replacing Me 2 NC(dS)Cl with ClC(dS)OC 6 H 4 -Me-4 led to [WCl(CO) 3 {HB(pz) 3 }] (12).

Highly distorted octahedral molybdenum(II) complexes: Synthesis, crystal structure, and properties of [Mo(S2C6H4)(CO)2(PMe Ph3−)2] (n= 0–3)

“…The starting material [Mo(g 3 -C 3 H 5 )(Br)(CH 3 CN) 2 (CO) 2 ] (labeled 5 in Scheme 1) was prepared by a slight modification of the method reported in literature [25], whereas the preparation of compound 6 followed the literature method [26]. After dissolving 5 in acetonitrile, PPh 3 was added to the yellow solution with stirring, and compound 6 was obtained as a yellow precipitate after heating under reflux for 30 min.…”

“…Trimethylphosphine [32] and [Mo(CH 3 CN) 2 (CO) 2 (PPh 3 ) 2 ] (compound 6) [26] were prepared according to literature methods.…”

Synthesis and Crystal Structures of the Molybdenum(II) Complexes with the N,N‐dimethylthiocarbamoyl Containing Ligand: Crystal Structures of β [Mo(CO)2{η2‐S2P(OEt)2}(η2‐SCNMe2)(PPh3)] and [Mo(CO)2(η3‐Tp)(η2‐SCNMe2)(PPh3)]

“…Treatment of complex [Mo(CO) 2 (h 2 -SCNMe 2 )-(PPh 3 ) 2 Cl] 1, with NH 4 S 2 P(OEt) 2 in dichloromethane at room temperature resulted in the chloride and triphenylphosphine displaced seven coordinated diethyldithiophosphate thiocarbamoyl-molybdenum complex, 13 The air-sensitive orange compounds b-3 and 4 are soluble in dichloromethane and ace-tonitrile, slightly soluble in methanol, and insoluble in diethyl ether and n-hexane.…”

“…7 Thiocarbamoyl Mo and W (VIB) complexes are known. [8][9][10][11] Our previous report 12 has shown that reaction of the thiocabamoyl-molybdenum complex [Mo(CO) 2 (h 2 -SCNMe 2 )(PPh 3 ) 2 Cl] 13 with pyridine-2-thionate, C 5 H 4 NS -, in dichloromethane at room temperature, yields the seven coordinated pyridine-2-thionate thiocabamoyl-molybdenum complex [Mo(CO) 2 (h 2 -SNC 5 H 4 )(h 2 -SCNMe 2 )(PPh 3 )] a-2. In complex a-2, the triphenylphosphine ligand and one carbonyl ligand are in the trans position.…”

Dicarbonylchlorido(phenoxythiocarbonyl-κ2C,S)bis(triphenylphosphane-κP)molybdenum(II)

“…For O-Aryl thiocarbonate, benzoxazoline-2-thione, chromene-2-thione and N,N-dimethylthiocarbamate metal complexes, see: Chen et al (1978); McFarlane et al (1998); Zheng et al (2006) and Zhang & Shi (2004), respectively. For phenoxylcarbonyl metal complexes, see: Anderson et al (2001). We are interested in the synthesis of dithiocarbamate, pyridine-2-thionate and N,N-dimethyldithiocarbarmoyl metal complexes.…”