Nucleophiles Derived from Group 15 N, P, As, and Sb

The anions derived from anilines are bidentate nucleophiles, and they can react through the N- or the C-atoms. For instances, 2-naphthylamide 57 anion reacted under photoinitiation with Arl in liquid ammonia to give l-aryl-2-naphthylamines 58 (C-arylation) in good yields and traces of N-arylated products 59 (Eq. 10.20) [49]. Double C-arylation was possible usingp-bromoiodobenzene as substrate and 57 to afford the disubstimtion product 60 [50]  

Following the same methodology, the photostimulated reaction of the anion of 9-phenanthryl amide with ArX gave 10-aryl phenanthren-9-amines (75-100%) [51].The double arylation of 9-phenanthryl amide with p-bromoiodobenzene afforded 40% yield of the disubstitution 

The regiochemistry of the coupling of Ar with different bidentate nitrogen heteroaryl anions has been investigated. For example, diverse arylpyrroles, arylindoles, and arylimidazoles are synthesized electrochemically by reaction of pyrrolyl [52], indolyl [53], and imidazolyl [52] anions in liquid ammonia with ArX with a C—C bond formation. The most reactive positions of nitrogen heteroaryl carbanions under conditions are the same as those observed in electrophilic substitution. For pyrrolyl ion, substitution at C-2 on the heterocycle is the main product [52]. For indolyl ions, substitution at C-3 is the major product observed [53]. The imidazolyl anion is the least reactive and leads to a mixture of arylation products at the C-2 and CA(5), where the 4-position was estimated to be about four times more reactive (Eq. 10.21) [53]  

In a similar procedure, electrochemically induced Sj l reactions have been employed for the synthesis of aryl uracils from ArX and the uracd anion 61 in DMSO (Eq. 10.22) [54], where the substitution always took place at the carbon leading to C-5-arylated uracils 62. This approach offers a mild method to obtain pyrimidine nucleosides substituted at the 5-position without requiring the preparation of specific reagents  

The (EtO)jPO ions react with ArX to yield the C—P bond (Ar-P(0)(OEt)j) under irradiation either in hquid ammonia, MeCN/THF, DMF, or DMSO as solvent [9, 55]. With substrates with two 

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