用Witting反应合成三苯甲基取代烯烃

第28卷第2期凌莹等:用Witting反应合成三苯甲基取代烯烃111化学试剂,2006,28(2),111~112用Witting反应合成三苯甲基取代烯烃凌莹,阳年发" ,杨利文,肖亮(湘潭大学化学学院,湖南湘潭411105)摘要:利用Wittig 反应,合成了(E)-5,5,5-三苯基-2-戊烯和2-甲基-5,5 ,5-三苯基-2-戊烯两种三苯甲基取代的烯烃。探讨了影响反应的各种因素,并找到了较好的合成条件。关键词:Wittig反应;三苯甲基;非官能团烯烃;制备中图分类号:0625. 12文献标识码:A文章编号:28328320020111-02含有大体积基团的烯烃是合成螺旋型手性聚产率63.1%。m.p.115~ 116C。'HNMR(CDClz),8:合物的重要单体[1],因为大体积基团的位阻作用1.49(d,3H,J = 6.3Hz);3.36(d,2H, J= 5.7Hz);可以使烯烃在其聚合过程中形成螺旋结构,因此5.28(m, 1H) ;5.36(m, 1H) ;7.18 ~ 7.32(m,15H)。近几年来这类化合物的合成引起了人们的关注。1.2.22-甲基-5,5,5-三苯基-2-戊烯 的合成，Okamoto2l在1990年用Wittig 反应制备了3,3,3-其合成方法与1.2.1合成方法相同。氮气保三苯基丙烯,然后用相似的方法又相继合成了4,护下将4.0g( 10mmol)异丙基三苯基溴化鏻悬浮于4,4三苯基-2-丁烯和1,1,1-三苯基2-戊烯两种三40mL无水四氢呋喃中，在-78C下缓慢滴加.苯甲基取代烯烃。我们利用Wittig 反应,合成了7.6mL 1.3mol/L的正丁基锂。滴毕，将反应混合两种新的三苯甲基取代烯烃(E)-5,5,5-三苯基-2-物置于室温下搅拌1h, 再将反应混合物冷至戊烯和2-甲基-5,5,5-三苯基-2-戊烯。- 78C,缓慢滴加20mL溶有2.0g(7mmol) 3,3,3-三苯基丙醛的四氢呋喃溶液。滴毕,在室温下继1实验部分续搅拌12h。后处理同1.2.1 ,得1.6g白色针状晶1.1主要仪器与试剂体,产率73.3%。m.p.80 ~ 82C。'HMR(CDClz),BrukerAV400核磁共振仪;X4型数字显示显8:1.39(s, 3H); 1.55(s, 3H);3.31(d,2H,J =微熔点测定仪(北京泰克仪器有限公司)。6.7Hz);5.02(t,1H,J = 6.7Hz);7.17 ~ 7.27(m,乙基三苯基溴化辚、异丙基三苯基溴化辚参15H)。照文献[3]自制;正丁基锂参照文献[4]自制;3,3,3-三苯基丙醛参照文献[5]自制;四氢呋喃(氮气2结果与讨论.保护下加金属钠回流,二苯甲酮为指示剂,蒸出后我们通过Wittig 反应合成了(E)-5,5,5-三苯备用);正己烷、正丙醇均为分析纯试剂。基-2-戊烯和2-甲基-5,5,5-三苯基-2-戊烯,反应式1.2合成方法如下。1.2.1 (E)-5,5,5-三苯基-2-戊烯 的合成CnHCHj(CH,),Br ncmhyu-CH,CH-iP(CH)s将3.9g( 10mmol)乙基三苯基溴化镤加人到THF100mL三口瓶中,氮气保护下加人40mL无水四氢PhyCCH2CHOhsCCH2呋喃,开动电磁搅拌使之溶解,在- 78C下缓慢滴CH,加7.6mL 1.3mol/L的正丁基锂,溶液逐渐变为桔(CH)2CHP(CH)Brn-CyHgLi-(CH)2C- -P(G&H),红色。滴毕,将反应混合物置于室温下搅拌1h,溶液变成暗红色。此时再将反应混合物冷至PhyCCH,HC- -C(CH)2- 78C ,缓慢滴加20ml溶有2.0g(7mmol) 3,3,3-三苯基丙醛的四氢呋喃溶液。滴毕,在室温下继.收稿日期:2005-06-11续搅拌12h。将反应液倒人40mL正己烷中,静置基金项目:国家自然科学基金(20472069)资助项目。2h,过滤除去沉淀,旋干滤液,剩余的油状物经冷作者简介:凌莹(1980-),女,浙江湖州人,硕士生,主要研究冻固化后用正丙醇重结晶,得1.3g白色粒状晶体，方向为有机合成。112化学试剂2006年2.1正丁基锂的用量对产率的影响[1]Nakano T,0kamoto Y . Synthetic helical polymers: Conforma-在合成这两种烯烃的过程中，发现正丁基锂tion and function[J]. Chem. Rev. , 2001 , 101 (12): 4013-的用量对产率是有影响的。当正丁基锂与季辚盐4038.[2]Shi Min, Okamoto Y . Photolysis of 1,1, 1-rayalk 2-enes and(乙基三苯基溴化镤或异丙基三苯基溴化辚)的物1,1, 1-tiaryhept-2-ynes. A novel generation of aryl( ak-1-质的量比小于1时,产率随正丁基锂用量的增加enyI) cearbenes and arl(alk-1-ymy1) carbenes[J]. J. Chem.而增加;反之,当正J基锂与季辚盐的物质的量比Soc. Perkin Trans. 1 , 1990:2443-2450.大于1时,产率随正丁基锂用量的增加而减少。[3]Fagerlund U H M, ldler D R. Marine sterols. IV .24-Dehydro-这可能是过量的正丁基锂使醛发生羟醛缩合副反cholesterol :Isolation from a barmacle and synthesis by the wit-应而导致产率下降。实验结果表明,正丁基锂与tig reaction[]. J. Am. Chem. Soc. , 1957 , 79(24):6473-季辚盐的最佳物质的量比为0.98。6475.2.2滴加3,3,3-三苯 基丙醛溶液的温度对产率[4]谢如刚.有机合成试剂制备手册[M].成都:四川大学出版社, 1988.7-78.的影响在10C滴加3,3,3-三苯基丙醛溶液时,未得[5]Curtn D Y, Hurvitz M J. Free radical rearangements in thedecarbonyaion of aldehydes[J]. J. Am . Chem . Soc. , 1952,到(E)-5,5,5-三苯基-2-戊烯和2-甲基-5,5,5-三苯74(21) :5381-5387.基-2-戊烯。温度在-90~-15C范围内变化时,产率降低比较平缓,温度高于- 15C后,产率降低The synthesis of tripbenylmethyl substituted olefn visa Witing较大。这可能是在较低的温度下抑制了3,3,3-三.reaction LING Ying， YANG Nianfa" ，YANG Li-wen, XIAO苯基丙醛发生羟醛缩合等副反应。iang ( Department of chemistry , Xiangtan University，Xiangtan反应结束后将反应混合物倒人正己烷中，411105 , China) , Huaxue Shji ,2006 ,28(2),111~ 112主要是为了使副产物三苯基氧化膦以沉淀的形式Abstract:( E)-5,5,5-triphenylpent-2-ene and 2-methy)-5,5,5-triphenylpent-2-ene were synthesized via Witig reaction.The fac-析出，以便通过过滤除去。静置2h,三苯基氧化tors affecting reaction were discussed and the optimum reaction膦已析出完全。conition was found.Key words: Witig reaction; triphenylmethyl; simple olefin;参考文献:preparation(上接第70页)Chemical Engineering, Anyan Institute of Technology ，Anyang[9]牛永生,邱明艳,李建平.芳酰基芳基偶氮化合物的合45000,0 China) , Huaxue Shiji , 2006 ,28(2) ,68 ~ 70;112成[J].应用化学,2005 , 22(1): 108-110.Abstrat:Thirteen acyldiazene compounds were synthesized. witha yield between 84% ~ 94% using sodium bromate as the oxida-Synthesis of acyldiazenes using NaBrO3/H,SO, as oxidationtion reagent in sulfuric acid . Their structures were confirmed byreagents NIU Yong sheng'.2 , U Jian-ping "' , ZHENG Peng- zhil'IR,' HNMR and elemental analysis . The reaction mechanism has(1. College of Chemistry and Environmental Science , Henan Nor-been discused.mal University , Key Laboratory of Environmental Pollution ContolKey words: acylhydrazines; acyldiazenes; NaBrOz/H2SO4; syn-of Henan Province , Xinxiang 453007, China; 2. Department ofthesis(上接第110页)(State Key Laboratory of Fine Chemicals, Dalian University of[6]Olah G A,Parker D C, Yoneda N,et al. OxfuntionalizationTechnology , Dalian 116012 , China)，Huaxue Shiji,2006, 28(2), .109~ 110;112of hydrocarbons. 1. Protolytic cleavage- rearrangement reac-Abstract: 8-Amyl hydroperoxide (TAHP) was synthesized by antions of tertiary alkyI hydroperoxides with magie acid[J].J.improved method using t-amy! alcohol, hydrogen peroxide andAm. Chem . Soc. ,1976,98(8) :2245-2250.sulfurie acid. The optimal condition is: temperature 35C , time[7 ]Philpotts A R, Thain W . Infrared absorption spectra of teriary2h, mol ratio 1:1:1.The reaction time was reduced from 24h toperoxides[J] . Anal. Chem. , 1952 ,24(4) :638-643.2h and the yield improved from 38% to 68% . The structure ofTAHP was identifed by IR,' HNMR and BCNMR.Improvement in synthetic method of t-amyl hydroperoxideKey words: t-amyl hydroperoxide; 8-amyl alcohol; synthesis;ZHOU Xin-rui* , U Jian-yuan, ZHAO Defeng, WANG LinTAHP