铬酸氢根季铵树脂对烯丙醇的选择性氧化

合成了铬酸氢根季铵盐树脂,以它作为一种选择性氧化剂应用于烯丙醇的氧化反应,考察了温度、时间、溶剂、树脂与醇的物料比对氧化反应的影响。在优化的反应条件下,即以苯为溶剂,n（树脂）：n（醇）=3．5：1,回流12h,丙烯醛产率达60．65％。实验表明,该季铵盐树脂能有效地将烯丙醇选择性地氧化为丙烯醛。     

From allylic alcohols to aldols by using iron carbonyls as catalysts: computational study on a novel tandem isomerization-aldolization reaction

The tandem isomerization-aldolization reaction between allyl alcohol and formaldehyde mediated by [Fe(CO)3] was studied with the density functional B3LYP method. Starting from the key [(enol)Fe(CO)3] complex, several reaction paths for the reaction with formaldehyde were explored. The results show that the most favorable reaction path involves first an enol/allyl alcohol ligand-exchange process followed by direct condensation of formaldehyde with the free enol. During this process, formation of the new C-C bond takes place simultaneously with a proton transfer between the enol and the aldehyde. Therefore, the role of [Fe(CO)3] is to catalyze the allyl alcohol to enol isomerization affording the free enol, which adds to the aldehyde in a carbonyl-ene type reaction. Similar results were obtained for the reaction between allyl alcohol and acetaldehyde.     

Allylation of alcohols and carboxylic acids with allyl acetate catalyzed by [Ir(cod)2](+)BF4- complex

A facile method for the synthesis of allyl alkyl ethers from alcohols with allyl acetate was developed by the use of [Ir(cod)(2)](+)BF(4)(-) complex. For instance, the reaction of allyl acetate with n-octyl alcohol in the presence of a catalytic amount of [Ir(cod)(2)](+)BF(4)(-) complex afforded allyl octyl ether in quantitative yield. Allyl carboxylates were also prepared by the exchange reaction between carboxylic acids and allyl acetate in good yields. The [Ir(cod)(2)](+)BF(4)(-) complex catalyzed the reaction of alkyl and aromatic amines with allyl acetate to lead to the corresponding allylamines in fair to good yields.     

Kinetics of Formation and Curing of Oligoether Urethane Allyl Ester

Kinetic parameters of formation of P-9AD oligoether urethane allyl ester with terminal double bonds and of its curing with dinitrile oxide were determined. The dependence of the rate constant on the allyl alcohol concentration and temperature was studied. The mechanism of reaction of P-9A prepolymer with allyl alcohol was proposed. The kinetic and thermodynamic parameters of curing of oligoether urethane allyl ester with dinitrile oxide were determined. The mechanism of reaction of P-9AD oligoether urethane allyl ester with dinitrile oxide was proposed.     

丙烯醇反马氏水合制备1,3-丙二醇

1,3-丙二醇具有很高的经济价值，是合成纤维聚对苯二甲酸丙二酯的重要原料。基于甘油甲酸介入法获得的丙烯醇作为平台分子，通过丙烯醇与TiCl4-NaBH4反应，首次实现常温常压下1,3-丙二醇的制备, 为1,3-丙二醇的合成提供了一条新的路径。在最优条件下，1,3-丙二醇的产率68.73%，推测反应机理为：TiCl4和NaBH4发生反应，生成中间体 “BH3”，进而实现了丙烯醇反马氏水合制备1,3-丙二醇。     

Rhodium‐Catalyzed Allylation of Aldehydes with Homoallylic Alcohols by Retroallylation and Isomerization to Saturated Ketones with Conventional or Microwave Heating

The treatment of an aldehyde with a tertiary homoallylic alcohol at 100–250 °C in the presence of cesium carbonate and a rhodium catalyst leads to allyl transfer from the homoallylic alcohol to the aldehyde. The process includes Rh‐mediated retroallylation to form an allyl rhodium species as the key intermediate. The homoallylic alcohol formed initially through allyl transfer is converted under the reaction conditions into the corresponding saturated ketone when bulky ligands are used. Microwave heating at 250 °C accelerates the reaction significantly.     

MoO3/SiO2催化甘油脱水氢转移还原制备烯丙醇

采用浸渍法制备了MoO3/SiO2催化剂,采用粉末X射线衍射、扫描电子显微镜、氮气吸附-脱附、NH3程序升温脱附及吸附吡啶傅里叶变换红外光谱等手段对催化剂进行了表征,并在固定床反应器中考察了催化剂负载量、反应温度、甘油浓度、空速等条件对MoO3/SiO2催化甘油制备烯丙醇反应性能的影响.结果表明,在MoO3的负载量(质量分数)为1%,330℃、常压、40%(质量分数)甘油水溶液和空速为200 h-1的反应条件下,甘油转化率、烯丙醇选择性及时空收率分别可达92.1%,34.8%和6.0 mmol.g-1.h-1.     

One-pot two-step reaction of selenosulfonate with isocyanides and allyl alcohol under aqueous conditions:Atom-economic synthesis of selenocarbamates and allyl sulfones

In many reactions involving selenosulfonate or thiosulfonate,the sutfone group often leaves in form of benzenesutfinic acid or sodium benzenesulfinate.A one-pot two-step reaction of selenosulfonate with isocyanides and allyl alcohol under aqueous conditions to afford selenocarbamates and allyl sulfone compounds is reported.The sulfinic acid as the first-step side product is converted to the allyl sulfone compound by water promoted reaction with allyl alcohol.Water acts as both an oxygen source of selenocarbamates and as a promoter to drive the second step reactio n.The reactions have the advantages of mild conditions,green,environment-friendly,and high atomic economy.     

烯丙基碘和锡与醛的选择加成反应

含活性基团的醛可与烯丙碘和锡粉直接进行亲核加成反应，得到高烯丙基的醇，水的存在不利于此反应的进行，与烯丙基溴相比，烯丙基碘反应活性更强，可在短时间内得较高的产率。     

Investigation of reaction routes for direct conversion of glycerol over zirconia?Ciron oxide catalyst

Conversion of glycerol to useful chemicals was examined using a zirconia?Ciron oxide catalyst. An aqueous glycerol solution was used as feedstock, and the catalytic reaction was carried out in a fixed-bed flow reactor at 623?K under atmospheric pressure. Useful chemicals, for example propylene, allyl alcohol, carboxylic acids, and ketones, were obtained from the aqueous glycerol solution. The reaction was found to involve a series of consecutive reactions, with allyl alcohol and carboxylic acids as reaction intermediates which were converted to propylene and ketones, respectively. Moreover, the catalyst had high and stable activity in the reaction of a 50 wt% glycerol solution.     

Scope of the allylation reaction with [RuCp(PP)]+ catalysts: changing the nucleophile or allylic alcohol

The scope of the dehydrative allylation reaction using allyl alcohol as allyl donor with [RuCp(PP)]⁺ complexes as catalysts is explored. Aliphatic alcohols are successfully allylated with allyl alcohol or diallyl ether, obtaining high selectivity for the alkyl allyl ether. The reactivity of aliphatic alcohols is in the order of primary > secondary ? tertiary. The tertiary alcohol 1‐adamantanol reacts extremely slowly in the absence of strong acid, but when HOTs is added, reasonable yields of 1‐adamantyl allyl ether are obtained. The alkyl allyl ether is found to be the thermodynamically favored product over diallyl ether. Apart from alcohols, thiols and indole are also efficiently allylated, while aniline acts as a catalyst inhibitor. Allylation reactions with various substituted allylic alcohols give products with retention of the substitution pattern. It is proposed that a Ru(IV) σ‐allyl species plays a key role in the mechanism of these allylation reactions. Copyright © 2010 John Wiley & Sons, Ltd.     

Stereoselective 4-benzyloxybut-2-enylation of aldehydes via an allyl-transfer reaction using a chiral allyl donor

[reaction: see text] A direct and highly stereoselective (E)-4-benzyloxybut-2-enylation of aldehydes was successfully carried out to give 5-benzyloxyhomoallylic alcohol (11) via an allyl-transfer reaction using a chiral allyl donor (10). The chiral allyl donor (10) was prepared by catalytic Sharpless asymmetric epoxidation of 3-methylbut-2-en-1-ol, followed by a stereospecific vinyl Grignard reaction of the epoxide in the presence of CuBr and selective benzylation of the primary alcohol of diol.     

无额外供氢体下负载型MoFeO_x催化剂催化甘油制丙烯醇

采用浸渍法制备MoFe/X(X=SnO_2,ZrO_2,CeO_2,TiO_2,CNTs,MgO)以及MoFe氧化物催化剂用于甘油气-固相催化转化制丙烯醇。通过XRD、BET、XPS、H_2-TPR和NH_3-TPD表征,MoFe主要由晶相Fe_2O_3和Fe_2(MoO_4)_3组成而MoFe/X主要为高分散态的Fe、Mo氧化物(Fe~(3+)、Mo~(6+)),其表面均只存在弱酸中心;所采用载体由于自身性质(比表面积和酸碱性)差异与Mo、Fe氧化物之间存在不同的相互作用,进而有效地调控了MoFe/X的表面弱酸强度、酸浓度和可还原性能。所制备催化剂对甘油制丙烯醇的催化性能(收率)依次为:MoFe/TiO_2MoFe/CeO_2MoFe/ZrO_2MoFe/CNTsMoFe/SnO_2MoFeMoFe/MgO。340°C时,MoFe/TiO_2上甘油的转化率达到83.4%,丙烯醇的选择性和收率分别达到26.7%和22.3%;同时其展现出优于MoFe/CeO_2、MoFe/ZrO_2和MoFe/CNTs的稳定性。甘油转化率与催化剂表面弱酸中心浓度呈正相关性,而丙烯醇的生成则与氧化中心(非酸中心)密切相关。甘油转化率和丙烯醇选择性在MoFe/X上随反应温度变化而呈现相悖的变化趋势。     

Pd-catalyzed domino carbonylative-decarboxylative allylation: an easy and selective monoallylation of ketones

In the presence of an allyl alcohol, α-chloroacetophenones undergo an allyloxycarbonylation reaction followed by in situ decarboxylative allylation to selectively afford the corresponding monoallylated ketones via a Pd-catalyzed domino sequence. The scope of the reaction was extended to substituted α-chloroacetophenones as well as various allyl alcohols.     

Mechanism of electroreduction of allyl alcohol at platinized platinum electrode in acidic aqueous solution.

The electroreduction of allyl alcohol to form propene at the platinized platinum electrode in acidic aqueous solution has been studied using CV plots, IR, ESR, and MS spectra, and a semiempricial MO method (MOPAC7/AM1, PM3). From the determinations of charge-transfer coefficients, reaction orders and apparent activation energy for the given reaction, the detection of the intermediates such as C(3)H(5)(+), C(3)H(5)(*), and C(3)H(5)(-) species, and PM3 calculations of charge distribution and frontier orbital energies of the reaction species C(3)H(5)OH and C(3)H(5)(+), the authors suggest that in acidic aqueous solution the production of propene via reductive splitting of the C-OH bond situated in the allyl position of allyl alcohol obeys a carbonium ion-carbanion mechanism.     

A tandem Finkelstein-rearrangement-elimination reaction: a straightforward synthetic route to allyl esters

Allyl esters can be obtained by a Finkelstein-rearrangement-elimination reaction of 2-chloro-1-(chloromethyl)ethyl esters induced by NaI. Sodium iodide can be used below equivalence using a reductive agent as sodium thiosulfate. High yields are obtained with most of the diverse esters studied. The method described avoids the use of allyl alcohol as a reagent. 2-Chloro-1-(chloromethyl)ethyl esters are prepared from glycerol, the main by-product of biodiesel industry. The effectiveness of iodine as reagent to hydrolyze allyl esters is also confirmed.     

Complexes de l'iridium avec le cyclooctadiène-1,5 IV. Le di-υ-chloro-bis(π-cylooctadiène-1,5)-bis(π-ether diallylique)-diiridium

Di-μ-chlorobis(π-cycloocta-1,5-diene)diiridium, (I), reacts with allyl alcohol to give a complex, (II), of (I) and diallyl ether and byproducts: propene, propanal and diallyl ether. The same complex is readily obtained by direct reaction of (I) and diallyl ether. Some physicochemical properties (II) are described (IR spectra, stability, reactivity, etc.). Its structure is discussed, and a mechanism for the transformation of allyl alcohol during the reaction is given.     

Reaction pathways of the Simmons-Smith reaction

The cyclopropanation reaction of an alkene with a metal carbenoid has been studied by means of the B3LYP hybrid density functional method. The cyclopropanation of ethylene with a lithium carbenoid or a zinc carbenoid [Simmons-Smith (SS) reagent] goes through two competing pathways, methylene transfer and carbometalation. Both processes are fast for the lithium carbenoid, while, for the zinc carbenoid, only the former is fast enough to be experimentally feasible. The reaction of an SS reagent (ClZnCH(2)Cl) with ethylene and an allyl alcohol in the presence of ZnCl(2) was also studied. The allyl alcohol reaction was modeled with an SS reagent/alkoxide complex (ClCH(2)ZnOCH(2)CH=CH(2)) formed from the SS reagent and allyl alcohol. Two modes of acceleration were found. The first involves the well-accepted mechanism of 1,2-chlorine migration, and the second involves a five-centered bond alternation. The latter was found to be more facile than the former and to operate equally well both with ethylene and with aggregates of SS reagent/alkoxide complexes. Calculations on the SS reaction with 2-cyclohexen-1-ol offer a reasonable model for the hydroxy-directed diastereoselective SS reaction, which has been used for a long time in organic synthesis.     

气态烯丙醇光异构化反应的理论研究

本文采用自洽场分子轨道UHF/6-31G从头计算法, 辅以能量梯度法研究气相烯丙醇光异构化反应的机理。全部优化了T1态势能面上反应物、过渡态、中间体和产物的几何构型。基于Fukui提出的内禀反应坐标理论(IRC)计算这一体系的反应途径, 并针对各驻点进行MP2/6-31G的相关能校正, 得到该反应在激发态进行并为一经历双自由基中间体的分步反应的结论。支持了实验工作者提出的机理。     

不饱和醇电还原质谱-电化学循环伏安(MSCV)法研究:I.烯丙醇的电还原

用MSCV法研究了烯丙醇在多孔Pt电极上0.5ol.dm^-3HCLO4中的电还原。烯丙醇电还原时主要涉及二类反应:烯丙基上C-OH断键生成丙烯; 丙烯进一步氢化生成丙烷。表征丙烯及丙烷的诸碎片M/Z的质谱电流(IM)-电极电位(Φ)扫描曲线线详细描绘了各分步反应的状况。在一定电位范围, 各M/Z的lgIM-Φ呈线性; 求得各有关M/Z的Tafel斜率。根据实验结果对反应机理进行了详细分析。