Base-Catalyzed Alkylation with Olefins

Abstract

Alkylation of 2-chlorophenol with isobutylene. The catalyst was prepared in the autoclave by heating 644 g. (5 moles) of 2-chlorophenol with 4.5 g. (V, formula wt.) of aluminum turnings. Alkylation with isobutylene was effected at 80-90°and the product worked up to give 550 g. (60%) of 2terí-butyl-6-chlorophenol (b.p. 123°at 30 mm.; n1 2D°1.5265).Anal. Caled, for Ci0Hi3C1O: Cl, 19.2. Found: Cl, 19.3. Proof of structure of 2-tert-butyl-6-chlorophenol. A portion of the product of the above experiment was chlorinated with sulfuryl chloride to yield 2,4-dichloro-6-ier<-butylphenol (for chlorination method see under structure proof of 2,6diisopropylphenol). The 2,4-dichloro-6-<eri-butylphenol was obtained in 54% yield (b.p. 134°at 15 mm., n2D°1.5421).Anal. Caled, for C10H12CI2O: Cl, 32.3. Found: Cl, 32.4. This material had physical properties and infrared spectrum identical with those of material obtained by the pyridine-catalyzed sulfuryl chloride chlorination of 2-terí-butylphenol.Alkylation of 2-ethylphenol with 1-butene. The catalyst was prepared in the autoclave in the usual manner by heating 357.4 g. (2.88 moles) of 2-ethylphenol (prepared as above) with 4 g. (0.15 formula wt.) of aluminum turnings. At a temperature of 215°the reaction mixture was alkylated with 1-butene at 200-500 p.s.i. over a 3-hr. period. Working up the product in the usual manner gave 300 g. (58%) of 2-ethyl-6-sec-butylphenol (b.p. 140-141°at 30 mm.; n2D°1.5153).

Base-Catalyzed Hydroamination of Olefins: An Environmentally Friendly Route to Amines

“…A concerted hydroamination process as shown in Scheme 11 is also likely. [16] The amination is strongly dependent on the pK a of the amine used; in general, the greater the pK a , the lower is the temperature required for the amination reaction. [16] This is because of the higher basicity or nucleophilicity of the metal amide complex (a) (Scheme 10) participating in the nucleophilic addition (step II).…”

“…[16] The amination is strongly dependent on the pK a of the amine used; in general, the greater the pK a , the lower is the temperature required for the amination reaction. [16] This is because of the higher basicity or nucleophilicity of the metal amide complex (a) (Scheme 10) participating in the nucleophilic addition (step II). Kinetic studies on the reaction of ethylene [15] with diethylamine show that the hydroamination reaction rate is first order with respect to the concentrations of both olefin and the catalyst and zero order with respect to the concentration of amine, indicating the nucleophilic addition of the metal amide to the olefin as the rate-determining step (step II).…”

“…Ethylenediamine yields a mixture of its di-, tri-, and tetraethylamines in equimolar amounts. Piperidine on reaction with ethylene (at 100 8C and 38 bar) forms N-ethylpiperidine in good yield (~80%) [16,21] using metallic sodium in the presence of traces of pyridine or by using C 5 H 10 NLi as the precatalyst (90% yield). [2a] Similarly, aniline is converted to N-ethylaniline using Na or NaNH 2 as precatalyst at 250 ± 300 8C and 50 ± 200 bar pressure.…”

“…[2a] Similarly, aniline is converted to N-ethylaniline using Na or NaNH 2 as precatalyst at 250 ± 300 8C and 50 ± 200 bar pressure. [16,22] The reaction temperature and pressure for the amination of ethylene can be considerably lowered by using alkali metal amides [15,16,23] and supported alkali metals as catalysts. [24] Since they operate at low temperatures these catalysts are particularly useful for the selective formation of monoalkylated amines.…”

Research Progress in Non-noble Metals Catalyzed Hydroamination of Alkyenes and Alkynes

“…1～5). 此类反应中, 胺 类的酸性越弱(pK a 越大, 共轭碱碱性越强), 脱氢后形成 的金属盐亲核性就越强, 反应所需要的温度就越低, 同 时反应速度也越快 [29] . 能使胺类脱氢的试剂有碱金属 单质、碱金属氢化物、烷基碱金属有机化合物等, 常用 的碱金属为锂和钠.…”