Q67 · CSIR-NET Chemistry, June 2015

Paper: CSIR-NET June 2015 · Subject: Inorganic Chemistry · Chapter: Organometallic Compounds · Topic: Cluster Compounds Wade Rules · Marks: 2 · Difficulty: Easy

Amongst the following
\[ \begin{array}{ll} \text{(A) } \left[\mathrm{Mn}\left(\eta^{5}\text{-}\mathrm{Cp}\right)(\mathrm{CO})_{3}\right] & \text{(B) } \left[\mathrm{Os}\left(\eta^{5}\text{-}\mathrm{Cp}\right)_{2}\right] \\ \text{(C) } \left[\mathrm{Ru}\left(\eta^{5}\text{-}\mathrm{Cp}\right)_{2}\right] \text{ and} & \text{(D) } \left[\mathrm{Fe}\left(\eta^{5}\text{-}\mathrm{Cp}\right)_{2}\right] \end{array} \]
the compounds with most shielded and deshielded $\mathrm{C}_{\mathrm{p}}$ protons respectively, are
(a)D and A
(b)D and B
(c)C and A
(d)C and B
Answer
Answer: A ✓ checked by 4AB · confidence medium
Explanation
Cp ¹H shifts: Cp₂Fe ≈ 4.04, Cp₂Ru ≈ 4.42, Cp₂Os ≈ 4.71, CpMn(CO)₃ ≈ 4.8 ppm (the CO groups withdraw electron density). So ferrocene is the most shielded and cymantrene the most deshielded (a).

Study loop for Organometallic Compounds

1. Practise the PYQsPrevious-year questions, with answers

· Browse this chapter in the app