Lithium hydroxide dimer

The molecular structure of Li2(0H)p(g) is assumed identical to that adopted for the higher alkali metal hydroxide dimers. It consists of a planar configuration for the lithium and oxygen atoms with the O-Li-0 bond angle equal to 90 . The hydrogen atoms are placed in a trans-configuration above and below the plane of the rhombus formed by the lithium and oxygen atoms. The Li-O-H... 

The transesterification reaction is rim at 230-250°C in the presence of a catalyst many catalysts have been used. Before the strict regulation of lead in coatings, litharge (PbO) was widely used the residual transesterification catalyst also acted as a drier. Examples of catalysts now used in the United States are tetraisopropyl titanate, lithium hydroxide, and lithium ricinoleate. The reaction is run under an inert atmosphere such as CO2 or N2 to minimize discoloration and dimerization of drying oils. Rather than using glycerol, the transesterification can also be carried out with higher functionality polyols such as pentaerythritol. 

Attempts to convert 1-bromo-l-phenylacetonitrile into the dicyano derivative under liquidrliquid two-phase conditions have been unsuccessful but, on addition of aqueous sodium hydroxide, l,2-dicyano-l,2-diphenylethene is formed by an oxidative dimerization mechanism [18], Similarly, diethyl bromomalonate fails to produce the corresponding azide with lithium azide under catalytic conditions the sole product (15%) is the ethene-l,l,2,2-tetracarboxylate [19]. 

Otherwise, lithium amides of secondary amines undergo anodic dimerization to form hydrazines in moderate yields [12]. Hydrazines are also generated, if secondary amines are electrochemically oxidized in the presence of an alkali hydroxide [27,28]. This reaction is mainly effective if the coupling takes place intramolecularly to give cyclic hydrazine derivatives [28]. If lithium amides of secondary amines are anodically oxidized in tetrahydro-furan (THF) solution in the presence of the free amine, 2-aminotetrahydrofurans are formed in reasonable yields. In contrast, the respective aminomagnesium bromides only gives A, A -coupling products [29]. 

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