The first selenium containing non-detergent sulphobetaines are described. They have been prepared in multi-gram quantities from readily available pyridyl precusors. Incorporation of selenium was achieved using nucleophilic organoselenide anions. The resulting products were shown by Se-77 NMR spectroscopy to be homogeneous with respect to selenium oxidation state. (C) 2003 Elsevier Ltd. All rights reserved.
The first selenium containing non-detergent sulphobetaines are described. They have been prepared in multi-gram quantities from readily available pyridyl precusors. Incorporation of selenium was achieved using nucleophilic organoselenide anions. The resulting products were shown by Se-77 NMR spectroscopy to be homogeneous with respect to selenium oxidation state. (C) 2003 Elsevier Ltd. All rights reserved.
result of an SN2 substitution process. Addition of -propyl iodide afforded the halogenopyridyl -propyl selenides. Treatment of these compounds with excess MeSeLi gave the (-propylselenenyl)pyridylselenolate anions which were directly treated with an alkylating agent and good yields of bis(alkylselenenyl)pyridines were obtained. All these nucleophilicaromaticsubstitutionreactions were completely regiospecific
几种二卤代吡啶与PhSeNa或HeSeLi在DMF中的反应提供了高产率的单取代产物。用过量的PhSeNa容易得到双(苯基硒烯基)吡啶,而用过量的MeSeLi,由于S N 2取代过程,最初形成的卤代吡啶基甲基硒化物而不是芳香族取代基发生脱烷基反应,得到卤代吡啶基硒酸根阴离子。加入-丙基碘化物,得到卤代吡啶基-丙基硒化物。用过量的MeSeLi处理这些化合物可得到(获得了直接用烷基化剂处理的-丙基硒烯基)吡啶基硒烯酸根阴离子,并获得了高产率的双(烷基硒烯基)吡啶。所有这些亲核芳族取代反应都是完全区域特异性的。
Kamiyama, Tsutomu; Enomoto, Saburo; Inoue, Masami, Chemical and pharmaceutical bulletin, 1985, vol. 33, # 12, p. 5184 - 5189
Kinetic and thermodynamic control in the metalation of pyridine. A direct synthesis of 2- and 4-substituted pyridines
作者:J. Verbeek、L. Brandsma
DOI:10.1021/jo00194a046
日期:1984.10
Dunne, Simon J.; Summers, Lindsay A.; Nagy-Felsobuky, Ellak I. von, Phosphorus, Sulfur and Silicon and the Related Elements, 1992, vol. 72, # 1-4, p. 103 - 120
作者:Dunne, Simon J.、Summers, Lindsay A.、Nagy-Felsobuky, Ellak I. von
DOI:——
日期:——
KAMIYAMA, TSUTOMU;ENOMOTO, SABURO;INOUE, MASAMI, CHEM. AND PHARM. BULL., 1985, 33, N 12, 5184-5189