Co-Investigator(Kenkyū-buntansha) |
AMEMIYA Ryo Tohoku University, Graduate School of Pharmaceutical Sciences, Instructor, 大学院・薬学研究科, 助手 (20359532)
ARISAWA Mieko Tohoku University, Graduate School of Pharmaceutical Sciences, Instructor, 大学院・薬学研究科, 助手 (50302162)
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Research Abstract |
Organoheteroatom compounds containing sulfur, selenium, phosphorous, or arsine (group 15 and 16 elements) are a group of useful compounds in the development of drugs and materials. It is therefore an important task of organic synthesis to develop effective synthetic methods for the compounds. Such compounds have been prepared by using the substitution reactions of organohalogen compounds with various heteroatom reagents, which were prepared from elemental sulfur or phosphorous. The methods, however, often employs toxic reagents and strict reaction conditions to remove trace of oxygen or moisture, and form metal halides as byproducts. The aim of the present project is to develop economical and environmentally benign synthetic methods for organoheteroatom compounds by employing addition reaction of elemental sulfur or phosphorous to unsaturated compounds. Reactions involving S-S bond cleavage of organic disulfides were investigated, and rhodium complexes were found to catalyze disulfide exchange reaction. The catalyst is also capable to exchange sulfur atoms between organic polysulfides and elemental sulfur. The results suggest that rhodium complex can be used for the activation of elemental sulfur. The method can be applied to the exchange reaction of an organic disulfide and an organic diselenide. It was also found that reaction of organic disulfide, diselenide, and 1-alkyne in the presence of rhodium complex provides the selenothiolated alkyne selectively. It is shown that the transition metal complex can discriminates sulfur and selenium atoms. A method was developed which catalyzes the addition of triphenylphosphine to ethylene, propylene, or 1-butene giving 1-alkylphosphonium salts. It is now shown that transition metal complex can effectively be used for various transformation of organosulfur and organophosphorous compounds.
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