Electrophilic Reagents - Electrophilic Reagents

They are also called electrophiles, electropositive reagents, or cationoid reagents. Lewis acids, i.e., cations or molecules with vacant orbitals that have high electron affinity, attack areas of high electron density or unshared electron pairs in a substrate. Examples of electrophiles include cations such as _H ⁺ , _NO2 ⁺ , _CH3CO ⁺ , _CH3 ⁺ , and _C6H5N2 ⁺ ; oxidizing agents such as _[ Fe(CN) ₆ ] ^3- , _SnCl4 , and Lewis acids such as _AlCl3 .

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

親電子試薬，陽性試薬，カチオノイド試薬などともいう．ルイス酸，すなわち陽イオンや電子親和力の大きい空軌道をもつ分子で，基質の電子密度の大きいところや非共有電子対を攻撃する．求電子試薬の例としては，H^＋，NO₂^＋，CH₃CO^＋，CH₃^＋，C₆H₅N₂^＋のようなカチオン，[Fe(CN)₆]^3－，SnCl₄のような酸化剤，AlCl₃のようなルイス酸などがある．

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