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121.
Masamitsu Shirai Masahiro Tsunooka Makoto Tanaka Kanji Nishijima Katsukiyo Ishikawa 《Journal of polymer science. Part A, Polymer chemistry》1989,27(1):325-332
Novel photosensitive polymers were synthesized by the copolymerization of methyl methacrylate and 1,2,3,4-tetrahydro-1-naphthylideneimino p-styrenesulfonate (NISS) and by the ternary polymerization of methyl methacrylate, methacrylic acid, and 9-fluorenylideneiminop-styrene-sulfonate (FISS). NISS and FISS units showed good sensitivity to light of wavelengths below 300 nm and below 366 nm, respectively. Although the polymers were insoluble in aqueous alkaline solutions, on irradiation with UV light they became soluble in aqueous alkaline solutions. A remarkable decrease in molecular weight of the polymers was observed during the photolysis of imino sulfonate groups incorporated into the polymers, which assisted the dissolution of the irradiated polymers. 相似文献
122.
Yoshiyuki Tanaka Makoto Arakawa Yohei Yamaguchi Chieko Hori Masahiro Ueno Takeyuki Tanaka Tatsushi Imahori Yoshinori Kondo 《化学:亚洲杂志》2006,1(4):581-585
A metal‐free acetylide was observed by using NMR spectroscopy. Metal‐free acetylides are closely related to reactive intermediates (carbanions) in solution; therefore, they have been regarded as unobservable species. However, we generated this highly reactive and unstable species through the deprotonation of phenylacetylene by using the strong nonmetallic phosphazene base tBu‐P4. In the presence of tBu‐P4, the J coupling between the ethynyl carbon and hydrogen nuclei (1JC,H) of phenylacetylene disappeared; this indicates the deprotonation of the alkyne terminal. Furthermore, a large low‐field shift (approximately 90 ppm) of the alkyne carbon resonance was observed. We concluded that we have observed a metal‐free carbanion with a formal charge on an sp‐hybridized carbon atom for the first time. 相似文献
123.
The ν2 (CD3 symmetrical deformation) and ν5 (CD3 degenerate deformation) fundamental bands of CD3Br were studied by 9.4- and 10.4-μm CO2 laser Stark spectroscopy. Stark resonances originating from 28 and 53 rovibrational transitions of the ν2 and ν5 bands, respectively, were assigned for each of the isotopic species, CD379Br and CD381Br. These two bands were simultaneously analyzed with explicit inclusion of the ν2-ν5 Coriolis interaction, yielding precise molecular constants in the ν2 and ν5 excited states as well as the Coriolis coupling constant. The molecular constants obtained are consistent between the two isotopic species and are in good agreement with the results of high-resolution infrared studies. The band origins and dipole moments are
CD379Br | CD381Br | |||||
991.396 82 (18) | 991.388 46 (17) | cm?1 | ||||
1055.469 00 (12) | 1055.466 32 (12) | cm?1 | ||||
1.830 42 (52) | 1.829 84 (47) | D | ||||
1.829 93 (48) | 1.829 57 (46) | D | ||||
1.832 23 (60) | 1.831 19 (56) | D |