Lithium phosphides reactions

Wright et al. have reported two cases where LiPHCy acts as a precursor to main group phosphinidine complexes. Reaction of the primary lithium phosphide with [AlMe N(mes) ]4 gives the heterometallic cage complex Li(THF) 4[ (AlMe)(ja-PCy) 2(ju.-PCy)]2 C6H5Me (95) (Fig. 12a). Reaction of [SnNBut]4 with 6 equiv of LiPHCy yields the complex cluster [ Sn2(PCy)3 2 Li(THF) 4], 2THF (96) (Fig. 12b). 

The reactions of lithium phosphides with chlorosilanes, which initially seemed so straightforward, turned out to be strikingly many-sided when PH-containing lithium phosphides are present. The formation of pure LiPH2 DME (DME = 1,2-dimethoxyethane) became feasible by coordination of a high boiling point ether (30). This method was employed by Klingebiel and collaborators (31) for the formation of... 

If for the reaction of Me2SiCl2 at 0°C a lithium phosphide is used, the latter formed by the introduction of excess PH3 in LiBu/hexane/Et20... 

It was not possible to obtain LisP by metallation of LiPHj with LiBu due to an ether cleavage reaction. Its formation succeeded through the reaction of PHj with an excess of LiBu in a solution of hexane/toluene and through the repeated action of LiBu on the lithium phosphide obtained initially (34). 

These two reactions, the substitution with elimination of LiCl and the PH lithiation by lithium phosphides, explain the formation of the compounds obtained in the reaction of Me2SiCl2 according to the reaction scheme of Scheme 7, in which all identified compounds are given a number. 

It is known from the preceding research that phosphorus-rich silylphosphanes or their related lithium phosphides undergo, with LiBu in ether, reactions in which a structural transformation occurs, as shown in Scheme 16 20). The reactions of the partially silylated tri- and cyclotetraphosphanes were explored in order to come closer to understanding the above reactions. It can be taken for granted that the P—C bond is not affected in such reactions. 

A. Reactions of Lithium Phosphides (MejSiljP—P(Li)—P(SiMe3) (CMej) AND [(MejCXMeaSilPliPLi in Ethers... 

Dibromoethylene, irradiation of, 5 156 Dibromomethylarsonic acids, 44 221 Dibromomethylsulfonium salts, 35 262 Di-(-butyldichlorosiIane, reactions, with lithium phosphides, 31 181-186 Dibutyl phosphonic acid, in liquid-liquid extraction, 9 34-35, 36-37... 

Silylated aminoiminophosphane, reaction with hexafluoroacetone, 30 238 Silylated cyclotetraphosphanes, 31 198 reactions with lithium alkyls and lithium phosphides, 31 204-212 Silylated tri- and tetraphosphanes reactions with lithium alkyls and lithium phosphides, 31 199-212 synthesis via lithiated diphosphanes, 31 194-198... 

A fascinating feature of the chemistry of boron-phosphorus heterocycles is the existence of stable singlet biradicals, e.g. fBuBP Pr2)2 (for a discussion of the electronic structure, see Section 5.4.2.2). The synthesis of this four-membered ring is illustrated in Scheme 5.2. Related derivatives of the type (RBPR 2)2 are also prepared by a salt-elimination reaction of the appropriate lithium phosphide with a 1,2-dichlorodiborane or, in the case of the perphenylated derivative (PhBPPh2)2, by reduction of the cyclic dimer [Ph(Cl)BPPh2]2 with lithium naphthalenide (Scheme 9.11). ... 

The lithium phosphide RP(SiMe3)Li has a stronger nucleophilic character than does RP(SiMe3)2. Moreover, in the silatropy reaction, in Scheme 7 the intermediate A is rather... 

During the reaction of the phosphaketene and lithium phosphide, an analogue to the well-known Peterson olefination, a lithium salt, can... 

Another possibility to generate phosphathioketenes on a larger scale for intercept reactions starts with the lithium phosphide [Eq. (80)]. Lithium phosphide reacts with CS2, which is inserted into the LiP bond... 

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