Efeitos Estéricos e Eletrônicos

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17.51 D D H + + 17.52 The amount of ortho product decreases as the size (steric bulk) of the alkyl group increases, indicating that the bromination reaction is somewhat subject to steric effects. 17.53 Both of these groups have a positively charged atom and thus should be inductive electron withdrawing groups. The S has an unshared pair of electrons, but, because of its positive charge, it does not want to donate them by resonance. Therefore, both groups should be deactivating and direct substitution to the meta position. 17.54 H₂C=CH(CH₂)₁₀CH₃ H₂SO₄ NaOH SO₃H 17.55 The nitroso group withdraws electrons by its inductive effect and donates electrons by its resonance effect. As was the case with the halogens, the inductive effect is controlling the rate of reaction and deactivating the compound, but the ortho and para positions are less deactivated due to donation of electrons back to those positions by resonance. 273