207923-99-7

Basic information

• Product Name: W(CO)2((η(2)-PCC6H2(t-Bu)3-2,4,6)W(CO)5)2
• CAS NO: 207923-99-7
• Molecular Weight: 1464.5
• Mol File: 207923-99-7.mol

Chemical Properties

• CAS DataBase Reference: W(CO)2((η(2)-PCC6H2(t-Bu)3-2,4,6)W(CO)5)2(CAS DataBase Reference)
• NIST Chemistry Reference: W(CO)2((η(2)-PCC6H2(t-Bu)3-2,4,6)W(CO)5)2(207923-99-7)
• EPA Substance Registry System: W(CO)2((η(2)-PCC6H2(t-Bu)3-2,4,6)W(CO)5)2(207923-99-7)

Safety Data

• Hazardous Substances Data: 207923-99-7(Hazardous Substances Data)

Upstream product

• 36477-75-5 tungsten pentacarbonyl tetrahydrofuran 
• 100938-86-1 2-(2,4,6-tri-tert-butylphenyl)phosphaacetylene 
• 110116-70-6 W₂(neopentoxide)6 

Relevant articles and documents

Different reaction modes of supermesitylphosphaalkyne with [W(CO)5thf]-unusual C-H-activation forming an indanyl substituent1

Treatment of the phosphaalkyne PCAr′ 1 with [W(CO)5(thf)] leads to the complex [W(CO)2{η2-PCAr′)W(CO)5}2] 2 (Ar′=C6H2tBu3-2,4,6) with two side-on coordinated phosphaalkyne moieties. In the presence of equimolar amounts of [W2(OtBu)6], however, the formation of [W(CO)4P(R′)C(Ar′)P{W(CO)5}] 3 (R′=2,4-tBu2-7-Me2-indanyl) is observed. 3 is a product of a 'head-to-tail' dimerisation of the former phosphaalkynes 1 to give a novel phosphinidene complex containing an indanyl substituent formed via C-H-activation.

An approach to novel complexes with a tungsten-phosphorus triple bond

The metathesis reaction of [W2(OtBu)6] with tBuC≡P leads to the phosphide complex [(tBuO)3W≡P] (1), which can be stabilized when the reaction is carried out in the presence of Lewis acidic carbonyl complexes of the type [M(CO)5thf] (M = Cr, W). However, further reaction of the metathesis products [(tBuO)3W≡CtBu] and [(tBuO)3W≡P→M(CO)5] [M = W (4a), Cr (4b)] with tBuC≡P leads after subsequent 1,3-OtBu shift to the metallaphosphacyclobutadiene derivatives [(tBuO)2W{C(tBu)}2P(OtBu)] (2a) and [(tBuO)2WC(tBu)P{M(CO)5}-P(OtBu)] [M = W (5a), M = Cr (5b)]. To prevent the latter, the bulky phosphaalkyne Ar′C≡ P (Ar′ = 2,4,6-tBu3C6H2) was employed in the three-component reaction instead of tBuC≡ P. Surprisingly here, a head-to-tail dimerization of Ar′C≡P occurs to give the novel phosphinidene complexes [M(CO)4P(R′)C(Ar′)P{MCO)5}] [M = Cr (6a), M = W (6b); R′ = 2,4-tBu2-7-Me2-indanyl]. In the case of [W(CO)5thf], additionally, the complex [W(CO)2{(η2-PCAr′)W(CO)5} 2] (7) is formed. The function of [W2(OtBu)6] in this reaction is uncertain, but stoichiometric amounts of [W2(OtBu)6] are essential to obtain complex 6. Reduction of the size of the alkoxide ligands by the use of [W2(ONp)6] (Np = CH2tBu) in the three-component reaction with Ar′C≡P leads to the trinuclear cluster compounds [W3〈(μ3-P)-{W(CO) 5}〉(μ-ONp)3(ONp)6] (8) and [W3(μ3-P)(μ-ONp)3(ONp)6] (9). The crucial step of the side-product free synthesis of the phosphido complexes 4 is the introduction of MesC≡P (Mes = 2,4,6-Me3C6H2) into the three-component system of [W2(OtBu)6], RC≡P, and [W(CO)5thf]. Comprehensive structural and spectroscopic data are given for the products. Furthermore, a 31P NMR experiment was conducted following the reaction of [W2(OtBu)6] with MesC≡P from -70°C to ambient temperature. In the range of -60 to -40°C, a singlet at 845 ppm with one pair of tungsten satellites (1JW,P = 176 Hz) was observed for the complex [(tBuO)3W≡ P] (1).