Argon-aniline complexes

The fluorescence excifafion spectra in Figures 9.47(a) and 9.47(b) show the Ojj bands of the A B2 X Ai system of aniline (see Figure 5.19) and the aniline Ar complex in a skimmed supersonic jet of aniline seeded into the argon carrier gas. 

The intramolecular cyclization of o-allylaniline derivatives (42) and (43) have been studied. The irradiations were carried out in hexane or acetonitrile and irradiation has supplied evidence for the involvement of intramolecular CT complexes. Irradiation of (42) affords the products (44) in the yields shown. The reactivity of (43) was also studied and its cyclization gave the analogous products (45). The influence of substituents on the photochemical reactions of some aniline derivatives (46) has been studied. The unsubstituted derivatives (46) predominantly undergo cyclization. The yield of product is dependent upon the mode of irradiation. Two conditions are described as (a) benzene/air and (b) ben-zene/argon. Under the aerated conditions oxidation of the cyclized product (47) occurs to yield (48). Cyclization is suppressed when the nitrogen is acylated these compounds (46, R = COMe) predominantly undergo a photo-Fries process to yield a mixture of the ortho and para products (49). Detailed studies showed that cyclization occurs from a CT state. 

Related carbodiphosphoranes of Cu(I)- and Au(I)-t-butoxide complexes (47) have been prepared and rigorously characterized. Both complexes were explored for the anti-Markovnikov hydroamination of acrylonitrile with aniline (Scheme 15.59). The Cu(I) system provided higher conversions to product over the Au(I) complex, and under the reaction conditions explored, only the Cu catalyst yielded high conversions under an argon atmosphere [257]. 

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