利用者:4dimp/下書き/隣接基関与

隣接基関与(りんせつきかんよ、英:Neighbouring group participation,NGP)とは、有機化学において反応中心の原子と孤立電子対の相互作用もしくはσ結合π結合の電子供与であるとIUPACによって定められている[1]。 Neighbouring group participation or NGP in organic chemistry has been defined by IUPAC as the interaction of a reaction centre with a lone pair of electrons in an atom or the electrons present in a sigma bond or pi bond [1]. When NGP is in operation it is normal for the reaction rate to be increased. It is also possible for the stereochemistry of the reaction to be abnormal (or unexpected) when compared with a normal reaction. While it is possible for neighbouring groups to influence many reactions in organic chemistry (For instance the reaction of a diene such as cyclohex-1,3-diene with maleic anhydride normally gives the endo isomer because of a secondary effect {overlap of the carbonyl group π orbitals with the transition state in the Diels-Alder reaction}) this page is limited to neighbouring group effects seen with carbocations and SN2 reactions.

ヘテロ原子の孤立電子対の隣接基関与[編集]

アルケンの隣接基関与[編集]

シクロプロパン,シクロブタン,ホモアリル基の隣接基関与[編集]

芳香環の隣接基関与[編集]

外部リンク[編集]

註釈[編集]

  1. ^ Advanced organic chemistry, page 314, Jerry March (4th Ed), Wiley-Interscience.