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Structures and reactions of CH3OCH2M (M = Li, Na, K) were investigated in a theoretical manner. CH3OCH2M has the acute bond angle of ∠M-C-O due to a strong coordination of the oxygen to the alkali metals. The nucleophilic substitution reaction of the substrate CH3OCH2Li by the nucleophile CH3OCH2Li is more preferred than the carbene generation by α-elimination and a nucleophilic substitution of CH3OCH2Li by CH3Li. The resulting 2-methoxyethyllithium readily liberated lithium methoxide to afford ethylene, which added to the anion species to give an ethylated product. Among the CH3OCH2M (M = Li, Na, K), CH3OCH2K is the most nucleophilic, due to the high σC–K level, while CH3OCH2Li is the most nucleophilic because of the lowest σ*C–O level. This supports a previously proposed mechanism for the ethylation of indole derivatives by methyl ethers in the presence of BuLi - t-BuOK.

We analyzed the bond interactions at the transition state of the Cope rearrangement of 1,5-hexadiene to disclose the significant participation of the geminal σ bonds at the reacting centers. The electron-donating σ bonds at the Z-positions and the electron-accepting σ bonds at the E-positions in the 1-substituted 1,5-hexadienes were predicted from the geminal bond participation to enhance the reactivities. For the reverse reactions, the 3-substituted 1,5-hexadienes were similarly predicted to rearrange more readily into the 1-substituted ones with the electron-donating σ bonds at the Z-positions. The predictions were confirmed by the density functional theory calculations.

A new synthetic procedure for the practical synthesis of β-trimethylsiloxyketones from silyl enol ethers and aldehydes has been described which heavily depends on organoaluminum reagent as an effective catalyst.