催化合成3-甲基-3-丁烯-1-醇醋酸酯及其水解过程研究

采用酯化水解两步法高效合成3-甲基-3-丁烯-1-醇(MBOH)。首先采用硅烷嫁接法制备了MCM-48嫁接SnCl2催化剂,应用于多聚甲醛、异丁烯和醋酸缩合酯化制备3-甲基-3-丁烯-1-醇醋酸酯(MB-AC),然后MB-AC碱性水解制备MBOH,并对缩合酯化和水解反应进行工艺条件考察。结果表明,最佳缩合酯化反应条件为:2.4 g催化剂,16 g多聚甲醛,120 g异丁烯,128 g醋酸,反应温度140℃,反应时间6 h。在此条件下,MB-AC的收率为55.5%,MBOH的收率为13.8%。进一步将缩合酯化反应产物碱性水解,最佳水解条件为:水解温度50℃,进料速度为60 mL/h,碱溶液质量分数为20%。在此条件下,水解收率为94.5%。酯化水解两步法制备MBOH的总收率达到65.5%。     

2-甲基-3-丁烯-2-醇合成3-甲基-2-丁烯-1-醇

[目的]2-甲基-3-丁烯-2-醇是异戊二烯间接皂化法生产3-甲基-2-丁烯-1-醇过程中产生的副产物,废物回收再利用是节能减排的有效措施.[方法]2-甲基-3-丁烯-2-醇经氯化、酯化和皂化得到3-甲基-2-丁烯-1-醇.[结果]结果表明:在优化条件下,氯化反应的产率可达87.25％,酯化和皂化反应的产率可达84.53％.[结论]该方法是2-甲基-3-丁烯-2-醇再利用的有效方法.     

3-甲基-2-丁烯-1-醇的催化水解工艺研究

以3-甲基-2-丁烯-1-氯为原料,合成3-甲基-2-丁烯-1-醇的催化水解工艺,利用气相色谱、红外光谱和核磁共振对所得产物进行了表征。通过正交试验讨论了催化剂种类、助催化剂种类、水解温度和水解液pH值对氯代烃的转化率和不饱和醇的选择性的影响。结果表明,最佳工艺条件为:n(氯代烃)∶n(CuCl)∶n(NaI)=1∶0.02∶0.02,水解温度为60℃,水解液pH=6。在此条件下,氯代烃的转化率达到97.83%,不饱和醇的选择性保持在94.19%。此外,研究了催化水解反应中副产物的产生机理及控制措施,提出了水解液循环利用过程中的催化效率保持的方法。     

3-甲基-3-丁烯-1-醇的合成

3-甲基-3-丁烯-1-醇通常采用多聚甲醛充分解聚完成后与异丁烯在有机碱催化下进行Prins反应得到。传统方法使用甲醇作为溶剂时,容易和甲醛缩合降低收率;而使用叔丁醇作为溶剂,回收时易凝固导致管道堵塞。采用甲缩醛作为溶剂不仅解决了上述问题,还在此基础上研究管式反应合成3-甲基-3-丁烯-1-醇,并对解聚条件和Prins缩合条件进行优化,得到最佳的反应条件。大幅减少了反应时间,反应效率提高。     

3-甲基-2-丁烯-1-醇的制备新工艺

研究了以溴代异戊烯水解工艺和精馏分离工艺为基础来制备3-甲基-2-丁烯-1-醇的新工艺。通过优化溶剂种类得到当水解溶剂为偶极类溶剂乙腈时,得到产物的选择性最高。并通过进一步优化实验操作条件,得到当溶剂加入量为v(乙腈):v(溴代异戊烯)=1:1,水解温度为70℃,碱用量为n(NaOH):n(溴代异戊烯)=1.2:1和反应时间为25min时,水解部分3-甲基-2-丁烯-1-醇的转化率最高可达63.35%。水解后的料液通过间歇精馏得到纯的3-甲基-2-丁烯-1-醇,最终的3-甲基-2-丁烯-1-醇总收率达到57.4%。     

3-甲基-2-丁烯-1-醇的合成方法

二氯菊酯是拟除虫菊酯杀虫剂的重要中间体。依据不同原料,介绍了其前驱体3-甲基-2-丁烯-1-醇三种合成方法,阐述了不同的合成方法得到的不同结果,比较了各种方法的可行性。重点介绍了以异丁烯应用普林斯反应的合成方法,其原料价廉易得,反应两步完成,副产物少,是主要的工业化生产方法。     

3-甲基-2-丁烯-1-醇的合成

以丙酮为原料,经羟醛缩合、脱水反应、卤仿反应和还原反应合成了3－甲基－2－丁烯－1－醇。     

甲醛异丁烯热缩合合成3-甲基-3-丁烯-1-醇的研究

以甲醇为溶剂,甲醛溶液和异丁烯为原料,通过Ene反应在无催化剂条件下合成了3-甲基-3-丁烯-1-醇(MBOH),系统考察了反应温度、反应压力、物料配比和反应时间对MBOH收率的影响。结果表明:一定温度是保证该反应进行的前提,当反应温度超过498 K后,MBOH的收率下降;反应压力对反应起促进作用,压力越大,MBOH的收率越高。在n(异丁烯)∶n(甲醛)=9∶1,反应温度为498 K,压力为11.0 MPa的最佳反应条件下,反应6 h后MBOH的收率可达59.24%。     

3-甲基-2-丁烯酸的合成研究

以廉价的2-甲基-3-丁炔-2-醇为原料,经迈耶-舒斯特重排反应得到3-甲基-2-丁烯醛,再经空气氧化制得标题化合物。对重排反应条件和氧化反应条件等工艺条件进行了详细研究。结果表明,以液体石蜡为溶剂,115～125℃催化重排反应3 h,处理后可得含量为98%的3-甲基-2-丁烯醛,收率85%以上;3-甲基-2-丁烯醛以微量氯化亚铜为催化剂,35℃以下通空气氧化,得到含量为97.5%的3-甲基-2-丁烯酸,收率90%以上。该方法原料廉价易得,工艺路线短,收率较高,对环境友好,是一种有前途的方法。     

Enhanced activity of MCM-48 based tin catalyst for synthesis of 3-methylbut-3-en-1-ol by adjusting the mesochannel environment

In the present work, tin incorporated MCM-48 catalysts were prepared by different strategies and applied in the synthesis of MB-AC and MBOH. The performance of the catalysts is strongly affected by mesochannel environment and acid texture. The organic-graft method (Sn-G-MCM-48) can modify the mesochannel environment and enhance the acid intensity and concentration (0.28 mmol/gcat), resulting in the improvement of the catalytic activity to the target reactions. The total yield of MB-AC and MBOH is as much as 68.4% over Sn-G-MCM-48 under mild conditions.     

3-甲基-2-戊烯-4-炔-1-醇的制备方法

3-甲基-2-戊烯-4-炔-1-醇是制备VA和虾青素的关键中间体,采用制备氯镁乙烯格式试剂与乙炔形成炔镁氯化物,与甲基乙烯酮进行缩合,水解引入两个碳原子转位重排蒸馏制备。     

Biosynthesis of 24-methylcholest-5-en-3β-ol and 24-ethylcholest-5-en-3β-ol inZea mays

The relative rates of synthesis of 24-methylcholest-5-en-3β-ol and 24-ethylcholest-5-en-3β-ol inZea mays shoots were determined using [2-¹⁴C]mevalonic acid and [methyl-¹⁴C]methionine as substrates. The 24-ethylsterol had a higher specific activity and it apparently was synthesized at about 3–4 times the rate of the 24-methylsterol.¹H NMR spectroscopy showed that the 24-ethylsterol was predominantly the 24α-epimer but the 24-methylsterol was a mixture of the 24α-epimer (30–40%) and the 24β-epimer (60–70%). The results are discussed in relation to the involvement of Δ²⁴⁽²⁸⁾-, Δ²³, Δ²⁵- and Δ²⁴⁽²⁵⁾-sterol intermediates in 24-methyl- and 24-ethylsterol production.     

1-Methylcyclohex-2-en-1-ol as an aggregation pheromone ofDendroctonus pseudotsugae

1-Methylcyclohex-2-en-1-ol (1,2-MCH-ol) was synthesized, identified as a compound found in volatiles of the female Douglas-fir beetle, and shown by bioassays to be an aggregation pheromone. 1,2-MCH-ol matches in both GC retention index and mass spectrum a compound released by the female after feeding. 3,3-MCH-ol was also synthesized as a candidate compound; its mass spectrum is presented because published mass spectra are incorrect for this compound. Synthetic 1,2-MCH-ol increased arrestment and stridulation of males in olfactory walkways and increased trap catches of flying beetles. Males were more responsive to 1,2-MCH-ol than females.     

多元电解质对脂肪酶有机相拆分炔戊醇的激活

脂肪酶是一种应用节广泛的重要生物催化剂,提高脂肪酶在非天然环境中的催化性能逐步成为了一个研究热点。研究表明,某些电解质的加入可显著提高提脂肪酶在有机溶剂体系中的酶活和选择性。然而有关研究主要考察单一电解质的作用,且涉及的电解质种类较少,更为系统的研究未见报道。本文以洋葱假单胞菌脂肪酶（Pseudomonas cepacia lipase,即PcL）催化手性菊酯农药前体4-甲基庚-4-烯基-1-炔基-3-醇（炔戊醇）在甲苯中选择性转酯化为模型,系统考察了卤化物、硝酸盐、硫酸盐、磷酸盐等8类35种电解质单独以及多种电解质协同对PcL催化性能的影响。结果表明,NaF-Na2HPO4/NaH2PO4的二元电解质体系具有远高于任意单一电解质组分的性能,该体系使PcL活力提高23倍。进一步研究表明,这一电解质体系对PcL催化不同对映体转酯化的活力提高程度不同,从而将其对映体选择率（E值）由11提高到21。     

(Z)-9-tetradecen-1-ol acetate

(Z)-9-Tetradecen-1-ol acetate [(Z)-9-TDA], identified originally as the sex pheromone of the fall armyworm,Spodoptera frugiperda (J.E. Smith), acted as a secondary sex pheromone when it was tested in sticky traps in field tests. Low-level synergism was obtained when 2 and 10% quantities of (Z)-9-TDA were added to 100 g of (Z)-9-dodecen-1-ol acetate, which is now considered the primary sex pheromone.Lepidoptera: Noctuidae.In cooperation with the University of Georgia College of Agriculture Experiment Stations, Coastal Plain Station, Tifton, Georgia 31794.Mention of a proprietary product does not constitute endorsement by the USDA.     

Occurrence of a novel sterol, 24,25-methylenecholest-5-en-3β-ol,inMortierella alpina 1S-4

24,25-Methylenecholest-5-en-3β-ol, which has not been reported previously to exist in nature, was isolated from mycelia of an arachidonic acid-producing fungus,Mortierella alpina 1S-4. Desmosterol, ergosta-5,24(25)-dien-3β-ol and ergosta-5,25-dien-3β-ol were also found in the fungus, but ergosterol and cholesterol were not detected. On leave from Suntory Ltd.     

Enzymatic conversion of 5α-cholest-8(14)-en-3β-ol to 5α-cholesta-8, 14-dien-3β-ol

[3α-³H]-Cholest-8(14)-en-3β-ol was incubated with a 10,000 x g supernatant fraction of a rat liver homogenate. The enzymatic formation of labeled cholesta-8, 14-dien-3β-ol was indicated by the results of studies employing column chromatographic and cocrystallization techniques.     

骨架镍催化1-环己烯乙腈选择加氢制备1-环己烯乙胺反应动力学研究

1-环己烯乙腈选择加氢是1-环己烯乙胺生产中的关键步骤之一。采用骨架镍催化剂在间歇高压釜中考察1-环己烯乙腈选择加氢制备1-环己烯乙胺的反应动力学。在消除内外扩散影响的条件下,通过测定催化加氢过程中1-环己烯乙腈浓度随时间的变化关系,获得了1-环己烯乙腈催化加氢动力学模型。动力学模型表明,1-环己烯乙腈选择加氢制备1-环己烯乙胺,对1-环己烯乙腈为零级反应而对氢压为一级反应。根据实验数据拟合出动力学参数,其中指前因子k0和活化能Ea分别为23.64和27.96 kJ mol 1。将动力学模型的方程、反应速率和反应物浓度的计算值和实验值进行比较,表明模型具有较高的拟合精度,能准确反映骨架镍催化1-环己烯乙腈选择加氢制备1-环己烯乙胺反应过程及其动力学特征。