Pyridine SrnI reaction

The pyrrolyl-pyridine and -quinoline precursors 1225 have been prepared via an electroinduced SrnI reaction in liquid ammonia by reacting pyrrolyl anions 1223 and the corresponding aryl halides 1224 (pyridyl and quinolyl chlorides) (Scheme 235) <2004S0517>. 

N-arylation product (151). Similarly, irradiation of para-chloro cyanobenzene or pyridine in the presence of 2.6-di-ferf.-butyl phenolate yields the biaryi (152). The SrnI reaction has been reviewed. 

Many reactions leading to heterosubstituted-arylphosphonic diesters have been described which fall within the general Scheme 6 of sequential photostimulated SrnI processes, where Ar is a benzene, naphthalene, or pyridine nucleus. Starting with the substituted (2-, 3-, and 4-) arylamine (124) pC = I, Br or (EtO)2P(0)], in reaction with KOP(OEt)2 [Nu(l)], and replacement of the amino group in (125) by a second replaceable group by classical methods, allows a second SrnI reaction to be then carried out on (126) with ArSH, KOP(OEt)2, C5H4NSH, C4H3N2SH, etc. [Nu(2)]." ... 

The photoinitiated reactions of 2-bromobenzonitrile and 2-bromo-3-cyano-pyridine with the carbanion of ethyl cyanoacetate afford the substitution product in good yields (90 and 80%, respectively) by an SrnI process. On the other hand, a non-chain radical nucleophilic mechanism is proposed to occur in the almost quantitative substitution of o-Cl, o-Br, and P-O2NQH4X (F, Cl, Br, I) with this anion in... 

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