1. NaBH RCH 4 2H+Ho≥RCH2OH 脱氧或加氢 an aldehyde 的反应 O 称为还原 H2NNH2 RCR HOA> RCHR a ketone O H2 crO4 RCH RCOH 加氧或脱氢 an aldenyde 的反应 称为氧化 OH O H2crO4 RCHR RCR an alcohol
脱氧或加氢 的反应 称为还原 加氧或脱氢 的反应 称为氧化
氧化-还原反应基本概念 if the number of c-h bonds has increased or the number of c-o c-n or c-x bonds has decreased the compound has been reduced. In other way round, the compound has been oxdized The oxidation state of a carbon atom equals the number of its C-o, C-N, or C-X bonds
一、氧化-还原反应基本概念 If the number of C If the number of C -H bonds H bonds has increased or the number increased or the number of C -O, C -N, or C -X bonds has decreased, the X bonds has decreased, the compound has been compound has been reduced reduced. In other way round, the compound has other way round, the compound has been oxdized oxdized. The oxidation state oxidation state of a carbon atom of a carbon atom equals the number of its C equals the number of its C -O, C -N, or C -X bonds. X bonds
Oxidation state(氧化态) oxidation reactions OXIDATION STATE 0 2 number of c-z bonds Z=O.N or halogen CH CH3OH HCH HCOH 0=C=0 CH3OCH3 CH3 CCH3 CH3COCH3 CH3OCOCH3 NCH3 O CH3CCH3 CH3 CNH2 CH3 OCNHCH3 OCH O CH3 CCH3(H) CH3 CCI CICCI OCH3 reduction reactions
Oxidation State（氧化态 ）
二、还原反应一催化氢化 the reduction by addition of two hydrogen Atoms(通过加氢的还原) can be carried out in the presence of a metal catalyst, so it is called Catalytic Hydrogenation(催化氢化) alkenes(C=C), alkynes(C=C) imines (C=N ),nitriles(C=N)Yes aldehydes or ketones(C=o) .But, RCOOH, RCOOR', and RCONHR'+No
二、还原反应 — 催化氢化 The reduction by addition of two hydrogen Atoms （通过加氢的还原）can be carried out in the presence of a metal catalyst, so it is called Catalytic Hydrogenation (催化氢化). alkenes ( C=C ), alkynes ( C ≡C ) imines ( C=N ), nitriles ( C ≡N ) aldehydes or ketones ( C=O ) Yes But, RCOOH, RCOOR’, and RCONHR’ No
二、还原反应一催化氢化 1机理 催化氢化的机理还没有完全研究清楚,通 常认为氢吸附在金属的表面,烯烃也通过 p-轨道与金属络合,然后烯烃与氢加成。 n其立体化学特征是—syn- addition H H H H H--C-C--H H H 题-8一题
二、还原反应 — 催化氢化 1. 机理 催化氢化的机理还没有完全研究清楚，通 催化氢化的机理还没有完全研究清楚，通 常认为氢吸附在金属的表面，烯烃也通过 常认为氢吸附在金属的表面，烯烃也通过 p -轨道与金属络合，然后烯烃与氢加成。 轨道与金属络合，然后烯烃与氢加成。 其立体化学特征是 其立体化学特征是 —— Syn -addition addition