On the reaction of (vinylimino)phosphoranes and related compounds. 20. Syntheses and properties of methanocyclodeca[b]pyridine ring systems
摘要:
Novel 2-[(triphenyl- and 2-[(tributylphosphoranylidene)amino]-1,6-methanol[10]annulenes (8x,y) and 3-[(triphenyl- and 3-[(tributylphosphoranylidene)amino]-1,6-methano[10]annulenes (9x,y) were generated by the Staudinger reaction of 2- and 3-azido-1,6-methano[10]annulenes (5 and 6). The compound 8x was inert to alpha,beta-unsaturated ketones, while compounds 8y and 9y were found to react with alpha,beta-unsaturated ketones in enamine-alkylation process followed by aza-Wittig reaction and dehydrogenation to give 7,12- and 5,10-methanocyclodeca[b]pyridines 20a-f and 26a,f, respectively. The reactivity of 8 and 9 as well as the site selectivity of 9 was suggested by their C-13 NMR spectra, in which the carbon signals of the nucleophilic center appear at higher field as compared to those of 1,6-methano[10]annulene. Structural properties of 20a-f and 26a,f were examined by H-1 NMR and UV spectra. The H-1 NMR spectra analyzing aromatic characters clarified both remarkable reduction of a ring current and appearance of bond alternation as compared to the parent 1,6-methano[10]annulene (1). The UV spectra exhibiting a prolonged cyclic conjugation are in contrast to their 10-pi electron analogues, 1,6-methano[10]annulene (1) and quinoline derivatives.
On the reaction of (vinylimino)phosphoranes and related compounds. 20. Syntheses and properties of methanocyclodeca[b]pyridine ring systems
摘要:
Novel 2-[(triphenyl- and 2-[(tributylphosphoranylidene)amino]-1,6-methanol[10]annulenes (8x,y) and 3-[(triphenyl- and 3-[(tributylphosphoranylidene)amino]-1,6-methano[10]annulenes (9x,y) were generated by the Staudinger reaction of 2- and 3-azido-1,6-methano[10]annulenes (5 and 6). The compound 8x was inert to alpha,beta-unsaturated ketones, while compounds 8y and 9y were found to react with alpha,beta-unsaturated ketones in enamine-alkylation process followed by aza-Wittig reaction and dehydrogenation to give 7,12- and 5,10-methanocyclodeca[b]pyridines 20a-f and 26a,f, respectively. The reactivity of 8 and 9 as well as the site selectivity of 9 was suggested by their C-13 NMR spectra, in which the carbon signals of the nucleophilic center appear at higher field as compared to those of 1,6-methano[10]annulene. Structural properties of 20a-f and 26a,f were examined by H-1 NMR and UV spectra. The H-1 NMR spectra analyzing aromatic characters clarified both remarkable reduction of a ring current and appearance of bond alternation as compared to the parent 1,6-methano[10]annulene (1). The UV spectra exhibiting a prolonged cyclic conjugation are in contrast to their 10-pi electron analogues, 1,6-methano[10]annulene (1) and quinoline derivatives.
On the reaction of (vinylimino)phosphoranes and related compounds synthesis and properties of novel 1,6-methanocyclodeca[b]cyclohepta[d]pyrrole
作者:Makoto Nitta、Hiroyuki Kawaji、Nobuhiro Kanomata
DOI:10.1016/0040-4039(92)88063-b
日期:1992.1
The title compound was synthesized by thermal reaction of 3-phosphoranylidene-amino-1,6-methano[10]annulene with 2-chlorotropone in a single step. The examination of 1H NMR spectrum revealed that there is little contribution of peripheral 18-π electron conjugation, but it is rather composed of 1-azaazulene and methano[10]annulene moieties.
一步合成3-膦亚基-氨基-1,6-甲基[10]环戊烯与2-氯四氢萘酮进行热合成。1 H NMR光谱的检查表明,外围的18-π电子共轭几乎没有贡献,但是它由1-氮杂氮烯和甲醇[10]环戊烯部分组成。