Basic power - Chemistry Fact Sheet - 2

Basic power - Chemistry Fact Sheet - 2

Basic power	Order	Why ?
1.		I > III > II	lone pair on N is not used in resonance of -electrons in I. In II lone pair of the ring is itself used in delocalisation while that of outside ring in III.
2.		I > II > III > IV	—OCH₃ is strong electron donating group. This is due to ortho effect, all the aniline are less basic than p-substituted aniline due to steric hindrance.
3.		I > II > III > IV	I (hyper conugation and induction) II (induction) IV (ortho effect), ortho effect normally decreases basic nature.
4.		II > I > III	In II there is sp³ hybridised C, In I, sp². NO₂ is electron withdrawing.
5.		III > I > II	lone pair on N is used in delocalisation of -electrons in aromatic amines while cyclohexyl is electron repelling (III); in II, lone pair on N is used by two benzene ring.
6.		I > II > III > IV	NO₂ is electron-withdrawing, thus nitro-anilines are less basic than aniline. IV is less basic than III because —NO₂ is closer and exerts a stronger inductive effect.
7.		III > I > II	phenyl and —COCH₃ are electronwithdra-wing and —C₆H₅ < COCH₃
8.		I < II < III	Electron donating nature of C₂H₅ > CH₃ So more basic strength.
9.		I < II < III	ortho effect in I.
10.		I < II < III	ortho effect in (I)