76372-80-0Relevant academic research and scientific papers
Synthesis and Properties of β-Phospha-trimethinecyanine Dyes with Indoline End Groups
Gamon, Norbert,Reichardt, Christian
, p. 2072 - 2094 (2007/10/02)
Reaction of 1,3,3-trialkyl-2-methyleneindolines 4 and 5 with phosphorus(III) halides yields, by a twofold nucleophilic substitution, the halogeno-phosphanes 6a-c, which in turn react with trimethyloxonium tetrafluoroborate to give the β-phospha-trimethinecyanine dyes 3a, b.These β-phospha-cyanines 3a, b are the first higher-methinylogous representatives of the phosphamonomethinecyanine dyes 1, synthesized in 1964 by Dimroth and Hoffmann as the first compounds containing phosphorus in the oxidation state +3 and with coordination number 2. - The 1H-, 13C-, 31P-NMR- as well as the UV/VIS spectra of these β-phospha-cyanines 3a, b and of the analogous β-"carba"-, β-aza- and β-arsa-trimethinecyanines are discussed with respect to their constitution, configuration, and ?-electron-density distribution.
