Application Synthesis of 2-Ethyl Hexanol CH3 CH2CH2 CH2-CHCH2OH CH3 CH2 CH2 CH2=CHCHO 异辛醇 CHOCH 3 CH2CH3 Target Molecules: iso-octyl alcohol 2 CHr CH2CH2 CHO CH3 CH2CH2CH2-CHCHO OH CH2CH
Application： Synthesis of 2-Ethyl Hexanol CH3 CH2 CH2 CH2-CHCH2 OH CH2 CH3 CH3 CH2 CH2 CH2 =CHCHO CH2 CH3 CH3 CH2 CH2 CH2 -CHCHO OH CH2 CH3 2 CH3 CH2 CH2 CHO Target Molecules: iso-octyl alcohol 异辛醇
1.1.1.2 Hetero-Condensation between different molecules O O ll RH2C-C—R+R"H2C一C-R"— a. Tollens condensation(hydroxymethylation) H-C-H甲醛与含α-H醛酮的多伦缩合反应(羟甲基化) NaoH Oxalate H-C-H+ CH3CCH340-42C HOH2C-CH2-C-CH3 H2C=CH-C-CH HO (45%) O HCHO c—CH2 NHCOCH3 NaHcO: O2N C— CHNHCOCH3 CH2OH
1.1.1.2 Hetero-Condensation RH2 C C R' O R''H2 C C R''' O + a. Tollens condensation (hydroxymethylation) H C H 甲醛与含α-H醛酮的多伦缩合反应 (羟甲基化) O CH3CCH3 O HOH2C CH2 C CH3 O H2C CH C CH3 O H C H O + NaOH Oxalate △ 40-42℃ (45%) -H2O O2N C CH2NHCOCH3 O O2 N C CHNHCOCH3 O CH2OH HCHO NaHCO3 between different molecules
Tollens condensation Definition: This reaction involves the condensation of formaldehyde with an aliphatic al dehyde having an a hydrogen, followed by a crossed Cannizzaro reaction to produce geminal bishydroxymethyl derivatives 定义:含有∝-氢的醛(或酮)在碱性催化剂[如ca(OH)2, K2cO3 NaHco3等]的存在下,用不含a氢的甲醛处理,在 醛、酮的-碳原子上引入羟甲基的反应称为多伦缩合反应, 实际上由醇醛缩合和交叉康尼杂罗反应结合而成。 原料:甲醛和醛(或酮) 产物:多元醇( Polyols) 创始人:德国化学家多伦斯(1891) (J山y30,1841- January31,1918)
Tollens condensation • 定义： 含有-氢的醛(或酮)在碱性催化剂 [如Ca(OH)2 , K2CO3 , NaHCO3 等] 的存在下，用不含α-氢的甲醛处理，在 醛、酮的-碳原子上引入羟甲基的反应称为多伦缩合反应， 实际上由醇醛缩合和交叉康尼杂罗反应结合而成。 • 原料：甲醛和醛 (或酮) • 产物：多元醇 (Polyols) • 创始人：德国化学家多伦斯 (1891) • (July 30, 1841 – January 31, 1918) • Definition: This reaction involves the condensation of formaldehyde with an aliphatic aldehyde having an - hydrogen, followed by a crossed Cannizzaro reaction to produce geminal bishydroxymethyl derivatives
Cannizzaro Reacton 2RCHO Oh RCHOH t Rcoo The Cannizzaro reaction is a chemical reaction that involves the base-induced disproportionation of an aldehyde lacking a hydrogen atom in the alpha position Cannizzaro first accomplished this transformation in 1853 when he obtained benzyl alcohol and benzoic acid from the treatment of benzaldehyde with potash(potassium carbonate) 康尼杂罗反应的底物结构特点:α位上无活泼氢的醛; 康尼杂罗反应的反应发生条件:浓NaOH或KOH(或醇); 康尼杂罗反应的产物结构特征:醇和酸
Cannizzaro Reacton 2RCHO + OH - RCH2 OH + RCOO - 康尼杂罗反应的底物结构特点：α-位上无活泼氢的醛； 康尼杂罗反应的反应发生条件：浓NaOH或KOH(或醇)； 康尼杂罗反应的产物结构特征：醇和酸。 The Cannizzaro reaction is a chemical reaction that involves the base-induced disproportionation of an aldehyde lacking a hydrogen atom in the alpha position. Cannizzaro first accomplished this transformation in 1853, when he obtained benzyl alcohol and benzoic acid from the treatment of benzaldehyde with potash (potassium carbonate)
Application Examples Usage: It is commercially used to produce polyols such as pentaerythritol and trimethy lolpropane CH2OH CH2OH Ca(OH)2 HCHO CH3CH +3 HCHO HOH2C-C—CHO HOH2C-C--CH2OH +(HCOO)2 Ca Ca(OH)2 CH2OH CH2OH季戊四醇(57% OH O OH Cao.ho 5 HCHO HCOoH(85%) OH OH
Application Examples O + 5 HCHO CaO, H2O O OH OH OH OH + HCOOH (85%) CH3CH O HOH2C C CHO CH2OH CH2OH HOH2C C CH2OH CH2OH CH2OH Ca(OH)2 HCHO + + (HCOO) 2Ca Ca(OH)2 季 戊 四 醇 3 HCHO (57%) Usage: It is commercially used to produce polyols such as pentaerythritol and trimethylolpropane