1、,What s Organometallic Compounds?,A carbon-metal bond,Sodium acetylide,Sodium ethoxide,The natures of CM bonds,The electronegativity ofthe metal,Depend on,Carbanions (负碳离子),10.2 Preparation of Organolithium and Organomagnesium compounds,Alkyl halide,Tetrahydrofuran THF (四氢呋喃),Anhydrous!,Butyl bromid
2、e,Butyllithium (80% -90%),Diethyl ether Et2O,Grignard reagents: Alkylmagnesium Halides,Phenyl bromide,Characteristics of the reactions: Alkyl groups: 1, 2 , 3 alkyl,cycloalkyl alkenyl, aryl,2. Reactivity:,4. Exothermic,3. Without substitutes:,V. Grignard and P. Sabatier 1912 Nobel Prize,Alkyl Alkeny
3、l or Aryl RI RBr RCl RF,Phenylmagnesium Bromide (95%),P223,7.4 Ch.P185(3),Grignard found that, in the presence of ether, magnesium reacts with alkyl and aryl halides at room temperature to form organo- magnesium compounds. These solutions,called “Grignard reagents“ react with most functional groups
4、in a synthetically useful way. For this discovery, tremendously usefulin laboratory and industrial synthesis,he was awarded the 1912 Nobel Prize in Chemistry(shared with Paul Sabatier,discoverer of catalytic hydrogenation).,Franois Auguste Victor Grignard,1871-1935,http:/www.nobel.se/chemistry/laure
5、ates/1912/grignard-bio.html,Acidity of hydrocarbon:,The stronger the acid is, the weaker the conjugate base is.,10.3 Carbanions as Brsted bases:,Basicity of anions:,Carey(4th): 547,Organolithium compounds and Grignard reagents as base:,RM reacts with much weaker acidthan H2O,Ch. P186,10.4.1 Synthesi
6、s of alcohols using Grignard reagents,Reactions with carbonyl compounds:,Grignard reagents react with Formaldehyde(甲醛 ) Primary alcohols:,B. Grignard reagents react with higher aldehydes secondary alcohols:,P296, 9.10,Example:,Synthesis of Acetylenic alcohols (炔基醇):,C. Grignard reagents react with k
7、etones Tertiary alcohols:,10.4.2 Retrosynthetic analysis (逆合成分析),Target Molecule,Precursors,n-BuMgX + CH3COCH3,n-BuBr + Mg,Elias James Corey 1928-,which changed the way organic chemists undertake the synthesisof complex natural products,the synthesis of longifolene, maytansine, the ginkolides, prost
8、aglandins and leukotrienes, the development of new synthetic methods, particularly using chiral catalysts, and the application of computers to synthesis design are among his most notable achievements. Corey has received many honors, including the Wolf Prize (1986), the National Medal of Science (198
9、8), the Japan Prize in Medicinal Science (1989) and the Nobel Prize in Chemistry (1990). Born in Massachusetts, Corey obtainedthe Ph.D. at M.I.T. (1951), was on thefaculty at the University of Illinois(1951-59) where he became full professor at the early age of 27, and since 1959 he has been profess
10、or at Harvard. His research associates (graduate students and postdoctoral fellows) number over 500 and populate the academic and industrial laboratories of Europe, Asia and the Americas.,Professor Corey (to collea- Gues and friends, E.J.) is known for his many spectacular contributions to synthetic
11、 organic chemistry. The concept of “retrosynthetic analysis“,Preparation of lithium dialkylcuprate reagents:,Coupling reactions of Organocoppers with Alkylhalides,Ch.P185 (3),10.4.3 Alkanes synthesis by using organocopper reagents,Characteristics of the reaction:,SN2 reaction The order of the reacti
12、vity : CH3 1 2 3I Br Cl F,2. To alkyl halides, R: primary,vinyl and aryl groups.To Lithium dialkylcuprate, R: primary group or -CH3.,12.44 Ziegle-Natta Catalysis of Alkene Polymerization,Ziegle catalyst: TiCl4-Et2AlCl,Ethylene Ethylene oligomers,Characteristics of the products: Ethylene oligomers wi
13、th 6-18 carbons High-density,G. Nattas contributions:,Isotactic polypropylene等规 (立构) 的聚丙烯,Carey:P567 14.15,Coordination polymerization 配位络合聚合,Polypropylene industry was started,K. Ziegle and G. Natta shared the 1963 Nobel Prize in Chemistry,Problems: Carey(4th)P573,14.15 (b), (d) 14.17 (h), (m), (n) 14.18 (d), (e) 14.19 (b), (f) 14.20 (d), (e) 14.21 (a)-(c) 14.22 (b), (f), (g) 14.23 14.25 14.26*(选作) 14.27,14.28 (b) 14.29,