Comment on the following:

(a) Infrared spectra of [V(CO)₆]⁻ and Cr(CO)₆ show absorptions at 1859 and 1981 cm⁻¹ respectively assigned to ν_CO, and 460 and 441 cm⁻¹ assigned to ν_MC.

(b) The Tolman cone angles of PPh₃ and P(4-MeC₆H₄)₃ are both 145°, but that of P(2-MeC₆H₄)₃ is 1948.

(c) Before reaction with PPh₃, Ru₃(CO)₁₂ may be treated with Me₃NO in MeCN.

(d) In the complex

the Os—C_ethyne—H_ethyne bond angle is 127°.

Transcribed Image Text:

2+ [Os(en) 2 (n²-C₂H4)(n²-C₂H₂)]²+