The reaction of molybdenum and tungsten carbyne complexes with sulphur and selenium; crystal structures of [Mo{η²-(S₂CCH₂Bu^t)}-(CO)₂(η-C₅H₅)] and [W{η²-(S₂CC₆H₄Me-4)}(CO)₂(η-C₅H₅)]

Selenoaroyl complexes of molybdenum

“…2 Whilst the isolation of this series established the viability of chalcoaroyl ligands, the methodology employed has not met with wider success e.g., the addition of elemental sulfur or selenium to group 6 alkylidynes provides dichalcocarboxylato complexes. 3 The addition of selenium 4 or tellurium 5 to bridging alkylidyne complexes has however provided binuclear selenoaroyl and telluroaroyl complexes and we have shown that methylthiirane serves as a single sulfur atom transfer reagent allowing access to thioaroyl complexes of molybdenum and tungsten. 6 The synthetic challenge would therefore appear to lie in identifying a suitable protocol to allow the transfer of a single selenium atom to an alkylidyne complex.…”

“…The 10 The second product of the reaction is the diselenocarboxylato complex [Mo(k 2 -Se 2 CR)(CO) 2 {HB(pz) 3 }] (3), spectroscopic data for which{ may be compared with the complexes [Mo(g 2 -Se 2 CCH 2 CMe 3 ){P(OMe) 3 } 2 (g-C 5 H 5 )] and [W(g 2 -Se 2 CC 6 C 4 Me)-(CO) 2 (g-C 5 H 5 )]. 3 Complex 3 was also structurally characterised in a study that confirmed the molecular geometry, however the precision of the model was compromised by unresolved systematic errors in the diffraction data precluding detailed discussion. Notably, it could be shown that heating 2 with either elemental selenium or alternatively with further SeCNR* led to clean conversion to 3.…”

Reactivity of [Cp*Mo(CO)3Me] with chalcogenated borohydrides Li[BH2E3] and Li[BH3EFc] (Cp*= (η 5-C5Me5); E = S, Se or Te; Fc = (C5H5-Fe-C5H4))

“…The Mo-S separation of 2.469(11) Å is slightly shorter than that observed in [CpMo(CO) 2 {η 2 -(S 2 CCH 2 t Bu)}] (2.477(1) Å). 26 The C8-S1 bond length is 1.666(3) Å, comparatively shorter than that observed for these types of complexes. Also, complex 2 possesses almost exact mirror symmetry (excluding Cp* ring).…”

Chemistry of polynuclear metal complexes with bridging carbene or carbyne ligands. Part 72. Di- and tri-metal compounds prepared from the alkylidyne tungsten complexes [W(CR)(CO)3{H2B(pz)2}][R = C6H4Me-4 or Me, H2B(pz)2= dihydrobis(pyrazol-1-yl)borate]

“…The corresponding reaction of (3b) with sulphur has not been studied, but [W(=cC6H,Me-4)(Co),(q-C,H,)] undergoes a similar reaction to yield [W(S,CC,H,Me-4)(CO),(q-C,H5)] (15b). 14 The 13C-(1H} n.m.r. spectrum of (15a) (Table 2) shows the absence of a resonance due to a W e nucleus.…”