Problem 1
Suggest products of the following reactions: (a) \(\mathrm{MeBr}+2 \mathrm{Li} \stackrel{\mathrm{Et}_{2} \mathrm{O}}{\longrightarrow}\) (b) \(\mathrm{Na}+\left(\mathrm{C}_{6} \mathrm{H}_{5}\right)_{2} \stackrel{\mathrm{THF}}{\longrightarrow}\) (c) \(^{n} B u L i+H_{2} O \rightarrow\) (d) \(\mathrm{Na}+\mathrm{C}_{5} \mathrm{H}_{6} \rightarrow\)
Problem 2
Whether the bonding in lithium alkyls is predominantly ionic or covalent is still a matter for debate. Assuming a covalent model, use a hybrid orbital approach to suggest a bonding scheme for (MeLi) \(_{4}\). Comment on the bonding picture you have described.
Problem 3
Describe the gas-phase and solid state structures of \(\mathrm{Me}_{2}\) Be and discuss the bonding in each case. Compare the bonding with that in \(\mathrm{BeH}_{2}\) and \(\mathrm{BeCl}_{2}\).
Problem 5
The compound \(\left(\mathrm{Me}_{3} \mathrm{Si}\right)_{2} \mathrm{C}(\mathrm{MgBr})_{2} \cdot n \mathrm{THF}\) is monomeric. Suggest a value for \(n\) and propose a structure for this Grignard reagent.
Problem 6
(a) For the equilibrium \(\mathrm{Al}_{2} \mathrm{R}_{6} \rightleftharpoons 2 \mathrm{AlR}_{3},\) comment on the fact that values of \(K\) are \(1.52 \times 10^{-8}\) for \(R=M e,\) and \(2.3 \times 10^{-4}\) for \(R=M e_{2} C H C H_{2} .(b)\) Describe the bonding in \(\mathrm{Al}_{2} \mathrm{Me}_{6}, \mathrm{Al}_{2} \mathrm{Cl}_{6}\) and \(\mathrm{Al}_{2} \mathrm{Me}_{4}(\mu-\mathrm{Cl})_{2}\).
Problem 7
Suggest products of the following reactions, which are not necessarily balanced on the left-hand side: (a) \(\mathrm{Al}_{2} \mathrm{Me}_{6}+\mathrm{H}_{2} \mathrm{O} \rightarrow\) (b) \(\mathrm{AlR}_{3}+\mathrm{R}^{\prime} \mathrm{NH}_{2} \rightarrow\) (c) \(\mathrm{Me}_{3} \mathrm{SiCl}+\mathrm{Na}\left[\mathrm{C}_{5} \mathrm{H}_{5}\right] \rightarrow\) (d) \(\mathrm{Me}_{2} \mathrm{SiCl}_{2}+\mathrm{Li}\left[\mathrm{AlH}_{4}\right] \rightarrow\)
Problem 9
The conversion of \(\left(\eta^{1}-\mathrm{C}_{5} \mathrm{Me}_{5}\right)_{2} \mathrm{SiBr}_{2}\) to \(\left(\eta^{5}-\mathrm{C}_{5} \mathrm{Me}_{5}\right)_{2} \mathrm{Si}\) is achieved using anthracene/potassium. Outline the role of this reagent.
Problem 10
Suggest the nature of the solid state structures of (a) \(\mathrm{Ph}_{2} \mathrm{PbCl}_{2}\) (b) \(\mathrm{Ph}_{3} \mathrm{PbCl}\) (c) \(\left(2,4,6-\mathrm{Me}_{3} \mathrm{C}_{6} \mathrm{H}_{2}\right)_{3} \mathrm{PbCl}\), and \((\mathrm{d})\left[\mathrm{PhPbCl}_{5}\right]^{2-} .\) In each case, state the expected coordination environment of the Pb centre.
Problem 11
Suggest products when \(\mathrm{Et}_{3} \mathrm{SnCl}\) reacts with the following reagents: (a) \(\mathrm{H}_{2} \mathrm{O} ;(\mathrm{b}) \mathrm{Na}[\mathrm{Cp}]\) (c) \(\mathrm{Na}_{2} \mathrm{S} ;\) (d) PhLi; (e) Na.
Problem 14
Discuss the bonding between the central \(p\) -block elements in the following compounds and give the expected arrangements of the organic substituents with respect to the central \(\mathrm{E}_{2}\) -unit: (a) \(\left[\left(2,4,6-\mathrm{Me}_{3} \mathrm{C}_{6} \mathrm{H}_{2}\right)_{2} \mathrm{BB}\left(2,4,6-\mathrm{Me}_{3} \mathrm{C}_{6} \mathrm{H}_{2}\right) \mathrm{Ph}\right]^{2-}\) (b) \(\left[\left(2,4,6-^{\mathrm{i}} \mathrm{Pr}_{3} \mathrm{C}_{6} \mathrm{H}_{2}\right)_{2} \mathrm{GaGa}\left(2,4,6-^{\mathrm{i}} \mathrm{Pr}_{3} \mathrm{C}_{6} \mathrm{H}_{2}\right)_{2}\right]^{-}\) (c) \(\left\\{\left(\mathrm{Me}_{3} \mathrm{Si}\right)_{2} \mathrm{CH}\right\\}_{2} \operatorname{SnSn}\left\\{\mathrm{CH}\left(\mathrm{SiMe}_{3}\right)_{2}\right\\}_{2}\) \((d)^{t} B u_{3} G e G e^{t} B u_{3}\) (e) \(\left(\mathrm{Me}_{3} \mathrm{Si}\right)_{3} \mathrm{CAs} \mathrm{AsC}\left(\mathrm{SiMe}_{3}\right)_{3}\)
