Racemization and Deracemization of Poly(quinoxaline-2,3-diyl)s

• Yoshihiko Ito

• Yutaka Kojima

• Masahiro Murakami

書誌事項

タイトル別名

• Racemization and Deracemization of Poly

抄録

Racemization of optically active oligo- and poly(quinoxaline-2,3-diyl) derivatives with a single screw-sense, prepared by the polymerization of 3,6-diaryl-1,2-diisocyanobenzenes catalyzed by methylpalladium(II) initiator, was investigated. Pentameric and hexameric oligomers with a living palladium terminus were reluctant to undergo racemization in solution at room temperature. However, the (oligoquinoxalinyl)bis(phosphine)palladium(II) complexes underwent a phosphine exchange reaction in the presence of an excess of phosphine ligand with partial racemization at room temperature. Oligomers without palladium terminus, prepared by a treatment of the corresponding palladium derivatives with methylmagnesium bromide, underwent racemization more rapidly, the rate of which depended upon the bulkiness of the substituents at the 5,8-positions of the quinoxaline rings and oligomerization degree, i.e., the number of the quinoxaline units in the oligomer chain. Starting from the racemic polymers with a living palladium terminus, substantial deracemization of the helical poly(quinoxaline-2,3-diyl) was induced by means of optically active 2,3-O-isopropylidenedioxy-1,4-bis(diphenylphosphino)butane ligand, which coordinated to the palladium terminus.

収録刊行物

• Bulletin of the Chemical Society of Japan

  Bulletin of the Chemical Society of Japan 70 (11), 2801-2806, 1997-11

  Tokyo : Chemical Society of Japan

キーワード

• General Chemistry

詳細情報

• CRID: 1521699229641847424
• NII論文ID: 10008925625
• NII書誌ID: AA00580132
• ISSN: 00092673
• ISSN: 13480634
• DOI: 10.1246/bcsj.70.2801
• NDL書誌ID: 4346215
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I4346215
• Web Site: https://academic.oup.com/bcsj/article-pdf/70/11/2801/56196187/bcsj.70.2801.pdf
• 本文言語コード: en
• NDL 雑誌分類:
  • ZP1(科学技術--化学・化学工業)
• データソース種別:
  • NDL
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  • CiNii Articles