Intramoleculare (4+2)-cycloadditionen mit inversem elektronenbedarf
作者:H Schuster、J Sauer
DOI:10.1016/s0040-4039(00)88268-4
日期:1983.1
1,2,4,5-Tetrazines, 1,2,4-triazines, α-pyrones and cyclopentadienones are reacted with bifunctional dienophiles 6 – 9 to yield semibullvalenes, snoutenes, azasnoutenes and polycyclic azo compounds or carbocycles in few steps.
Substituierte alfa-Pyrone und Verfahren zu deren Herstellung
申请人:CIBA-GEIGY AG
公开号:EP0369941A2
公开(公告)日:1990-05-23
α-Pyrone der Formel I
worin R¹ Cl oder Br und R² H, Cl oder Br sind. Das Halogen in 4-Stellung kann z.B. durch Alkoxy, Alkylthio oder Sekundäramino ersetzt werden. Die α-Pyrone eignen sich als Dienkomponente für Diels-Alder-Reaktionen.
METAL CATALYST FOR RING-OPENING POLYMERIZATION OF HETEROCYCLIC COMPOUND
申请人:SANYO CHEMICAL INDUSTRIES, LTD.
公开号:EP1340780A1
公开(公告)日:2003-09-03
The object of the present invention is to provide a metal catalyst which allows the production of a ring-opened polymer available from a heterocyclic compound, having primary terminal heteroatomic groups (terminal hydroxyl groups, in particular) in a ratio exceeding 75%.
The above object can be attained by using a metal catalyst comprising a ligand and a metal atom for ring-opening polymerization of heterocyclic compounds
in which, of all maximum angles (D) meeting the following definition, the smallest maximum angle (Dm) is not larger than 60 degrees;
The maximum angle (D) is the largest angle between an imaginary line (X) and an imaginary line (Y) of all the angles which can be assumed in a metal catalyst comprising a ligand and a metal atom,
said imaginary line (X) means a line perpendicular to an imaginary plane (P) including the respective centers of 3 coordinating atoms among those directly coordinating the metal atom (M) and not substitutable by a reaction substrate (S) and passing through the center of the metal atom,
said imaginary line (Y) means a line linking the center of a non-coordinating atom in the ligand and the center of the metal atom,
and said maximum angle (D) exists in a number equal to the number of non-coordinating atoms, that is, the number of imaginary lines (Y).
Metal catalyst for ring-opening polymerization of heterocyclic compound
申请人:——
公开号:US20040030093A1
公开(公告)日:2004-02-12
The object of the present invention is to provide a metal catalyst which allows the production of a ring-opened polymer available from a heterocyclic compound, having primary terminal heteroatomic groups (terminal hydroxyl groups, in particular) in a ratio exceeding 75%.
The above object can be attained by using a metal catalyst comprising a ligand and a metal atom for ring-opening polymerization of heterocyclic compounds
in which, of all maximum angles (D) meeting the following definition, the smallest maximum angle (Dm) is not larger than 60 degrees;
The maximum angle (D) is the largest angle between an imaginary line (X) and an imaginary line (Y) of all the angles which can be assumed in a metal catalyst comprising a ligand and a metal atom,
said imaginary line (X) means a line perpendicular to an imaginary plane (P) including the respective centers of 3 coordinating atoms among those directly coordinating the metal atom (M) and not substitutable by a reaction substrate (S) and passing through the center of the metal atom,
said imaginary line (Y) means a line linking the center of a non-coordinating atom in the ligand and the center of the metal atom,
and said maximum angle (D) exists in a number equal to the number of non-coordinating atoms, that is, the number of imaginary lines (Y).