Organolead Pseudohalides

A number of new organolead pseudohalides are reported in the recent literature. These include derivatives of fulmic acid HCNO, dicyanamide HN(CN)2 and tricyanomethane HC(CN)3. The organolead pseudohalides listed in Table 283 are prepared by the following methods. 

By rxn. of Se(SeCN)2 with Ph4Pb in refluxing HCCI3, in 8l% yield (697), with PhePba In HCCI3 at r.t., in 58% yield (697). 

By rxn. of PhsPbCl with KSeCN in EtOH in presence of KOAc, in 757. yield (697). Prop. White cryst., IR spectrum, soly., stable in air, struct. (697). 

IR spectrum (1127), exists in three polymorphic forms (9O3), differential thermal analysis (9O3, 2667), thermal gravimetric analysis (2667). 

The characters used here correspond to the synthetic scheme in the introduction to Chapter. 2.1. 

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Organolead compounds are best stored under an inert atmosphere at 0 . Many are light-sensitive. Tetraorganoplum-banes, and organolead halides, pseudohalides, sulfides, oxides, carboxylates and sulfonates can usually be handled in air. Other types of compound should be handled under an inert atmosphere. The thermal stability of organolead compounds tends to be quite low (ca. 100 ). 

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