The photochemistry of the α-bis(methoxyimino)alkanes 1–5 and the, structurally related, conjugated dihydro(methoxyimino)isoxazoles 6 and 7 was studied. Triplet-photosensitized irradiation of 1–7 leads only to stepwise E-Z isomerization. Photostationary-state (pss) ratios for 1,6 and 7 are reported for the various applied triplet sensitizers. Direct irradiation with 254 nm leads to both E-Z isomerization
UV spectroscopy and structures of α-bis(methoxyimino)alkanes
作者:Frank Stunnenberg、Hans Cerfontain、Kees Goubitz、Dick Heydenrijk、Caspar H. Stam
DOI:10.1002/recl.19921110105
日期:——
The UV spectra of the geometric isomers of the α-bis(methoxyimino)alkanes I-8 and the structurally related conjugated (methoxyimino)isoxazolines 11 and 13 all exhibit a ππ* absorption band, of which the maxima with cyclohexane as solvent are between 216 and 268 nm, and 258 and 282 nm, respectively. The differences in λmax are discussed in terms of variations in the degree of inter-iminyl conjugation