217479-82-8Relevant articles and documents
Investigations on systems of the type PCl3/MCl3/arene (M = Al, Ga), I. Reactions with monohalobenzenes; multinuclear NMR spectroscopic characterization of aryldichlorohydrogenphosphonium salts; crystal structure of para-fluorophenyldichlorophosphonium tetrachloroaluminate
Frank, Walter,Gelhausen, Bj?rn,Rei?, Guido J.,Salzer, Risto
, p. 1149 - 1168 (2007/10/03)
The reactions of the monohalobenzenes with AlCl3 (GaCl3) and PCl3 have been monitored by 31P NMR spectroscopy. Primary product of the reaction with fluorobenzene and AlCl3 is the thermolabile para-fluorophenyldichlorophosphonium tetrachloroaluminate, which was characterized by 1H, 13C, 19F, 27Al and 31P NMR spectroscopy as well as by a crystal structure analysis (space group P21/c, a = 7.0720(10), b = 12.659(3), c = 15.413(3) ?, β = 90.93(3)°, Z = 4, T = -110 °C). For the phosphonium ion we found a very good agreement of the experimental structural parameters and those obtained by ab initio quantum chemical calculations at the B3LYP 6-31++G(d,p) level of theory. Both, the experimentally determined and the calculated structure show a significant chinoid distortion of the para-disubstituted benzene ring. From the primary product the reaction proceeds to give exclusively para-fluorophenyl-(phenyl)dichlorophosphonium tetrachloroaluminate. With GaCl3 and fluorobenzene analogous tetrachlorogallates were observed, however, some by-products were recognized: para-fluorophenylchlorofluorophosphonium and para-fluorophenyldifluorophosphonium tetrachlorogallate at the beginning of the reaction, bis(para-fluorophenyl)chlorophosphonium tetrachlorogallate at a later stage of the reaction. The reaction of chlorobenzene with PCl3 and AlCl3 yields analogous products as compared to the reaction with fluorobenzene. However, appreciable amounts of ortho- and some meta-chlorophenyldichlorophosphonium tetrachloroaluminate are by-products. If GaCl3 is used instead of AlCl3, numerous by-products and reaction intermediates are detectable. The major one is para-chlorophenyldihydrogenchlorophosphonium tetrachlorogallate. No principal differences were observed, when AlCl3 and GaCl3, respectively, reacted with bromobenzene and PCl3 giving phenylbromodichlorophosphonium and para-bromophenylbromodichlorophosphonium salts as well as some amounts of the ortho- and meta-bromophenyl derivatives. With iodobenzene the corresponding reactions exclusively give phenyldichloroiodophosphonium tetrachloroaluminate and -gallate, respectively.