The Study of Alcoholysis of 1,2-Thiazetidine-l,l-dioxide with Quantum Chemical Method

The alcoholysis mechanism of 1,2-thiazetidine-1,1-dioxide with methanol, in which the relatively stable product is sulfonate ester, has been investigated by quantum chemical method. Our calculations indicate the reaction for alcoholysis of 1,2-thiazetidine-1,1-dioxide proceeds via two possible mechanisms: concerted and stepwise. In the stepwise mechanism, two possible reaction pathways can be followed while only one possible reaction pathway can be followed in the concerted mechanism.     

Formal Addition of β-Acylalkenyl Anions to Ketones Utilizing [1,2]-Phospha-Brook Rearrangement under Brønsted Base Catalysis

A methodology for the formal addition of β-acylalkenyl anions was developed by utilizing the [1,2]-phospha-Brook rearrangement under Brønsted base catalysis. The two-step reaction involves the catalytic addition of α-oxygenated propargyl anions generated via [1,2]-phospha-Brook rearrangement to electron-deficient ketones and subsequent alcoholysis to afford tertiary alcohols having an enone moiety. This is a rare example of a catalytic carbon-carbon bond forming reaction of β-acylalkenyl anion equivalents, providing synthetic building blocks that are otherwise difficult to access.     

Synthesis and properties of 2-ethyl-1-butyl-5-oxo-1,2-azaphospholane

Conclusions The hydrolysis, alcoholysis, aminolysis, and acidolysis of 2-ethyl-1-butyl-5-oxo-1,2-azaphospholane proceeds with cleavage of the nitrogen-phosphorus bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2059–2064, September, 1972.     

A highly efficient protocol for regioselective ring-opening of epoxides with alcohols,water, acetic acid,and acetic anhydride catalyzed by SbF3

SbF₃ as an efficient catalyst has been used for regioselective alcoholysis, acetolysis and hydrolysis of epoxides to the corresponding β-alkoxy, β-acetoxy alcohols, and 1,2-diols in high to excellent yields. This study also represents a convenient synthesis of vic-diacetates from ring-opening of epoxides with acetic anhydride.     

Calorimetric analysis of the ethanolysis of 1,2-epoxybutane

Polyethers, which are produced by alcoholysis of oxiranes, are often used as solvents in chemical plants. The spectra of the products can be influenced by the choice of the catalyst (acid or base). The results of the base-catalyzed ethanolysis of 1,2-epoxybutane are displayed. The reaction was investigated calorimetrically by varying the molar ratio between ethanol and 1,2-epoxybutane, the starting temperature and the concentration of the catalyst sodium hydroxide. Additionally, the influence of the used alcohol will be shown in one example. To determine the activation parameters, the experiments were evaluated by the nonlinear software package TA-kin v3.3.     

Lipase-catalyzed alcoholysis of diol dibenzoates: selective enzymatic access to the 2-benzoyl ester of 1,2-propanediol and preparation of the enantiomerically pure (R)-1-O-benzoyl-2-methylpropane-1,3-diol

Enzymatic debenzoylation of 1,2-propanediol dibenzoate with 1-octanol has been studied in organic solvent using lipases from different sources. In general a slow, highly regioselective alcoholysis in diisopropyl ether affords exclusively a monoester benzoylated at the secondary hydroxy group although the reaction proceeds with low enantioselectivity. In the presence of Pseudomonas cepacia lipase absorbed onto celite, a faster reaction allows the preparation of the 2-benzoyl ester of (R)-1,2-propanediol (82% ee) and the enantiomerically pure (R)-1-O-benzoyl-2-methylpropane-1,3-diol (>98% ee).     

A family of novel bifunctional organocatalysts:Highly enantioselective alcoholysis of meso cyclic anhydrides and its application for synthesis of the key intermediate of P2X7 receptor antagonists

A family of novel squaramides/sulfamides based on 1,2-alkamine was developed as chiral bifunctional catalysts to promote the asymmetric alcoholysis of meso cyclic anhydrides.The hemiesters were obtained in high yield with up to 93%ee.The usefulness of this methodology was demonstrated in the asymmetric synthesis of the key intermediate of P2X₇ receptor antagonists.     

Zirconyl triflate, [ZrO(OTf)2], as a new and highly efficient catalyst for ring-opening of epoxides

A highly efficient method for the ring opening of epoxides catalyzed by ZrO(OTf)₂ was adopted. This catalyst efficiently catalyzed alcoholysis, acetolysis and hydrolysis of epoxides and the corresponding alkoxy alcohols, acetoxy alcohols and 1,2- diols were obtained in excellent yields. Conversion of epoxides to 1,2-diacetetes, thiiranes and 1,3-dioxolanes was also performed in the presence of catalytic amounts of ZrO(OTf)₂, and the corresponding products were obtained in high to excellent yields. The high catalytic activity of ZrO(OTf)₂ is due to the replacement of Cl with OTf, which makes the ZrO(OTf)₂ as efficient Lewis acid.     

Ring opening of epoxides with alcohols using Fe(Cp)2BF4 as catalyst

Fe(Cp)₂BF₄ is an efficient catalyst for the alcoholysis of aromatic, aliphatic, and cyclic epoxides giving excellent yields of the corresponding β-alkoxy alcohols under ambient conditions. The methanolysis of styrene oxide using Fe(Cp)₂BF₄ as a catalyst (5 mol %) gave excellent yield of 2-methoxy-2-phenylethanol with complete regio-selectivity. The ring opening of cyclic epoxides gave 77–97% yields of trans-β-methoxy alcohols, in 0.5–6 h. The use of 1,2-epoxyhexane and 1,2-epoxydodecane as substrates gave both regioisomers in excellent yields. The first order rate of reaction with respect to catalyst was observed for the kinetics of ring opening of 1,2-epoxyhexane with methanol.     

Catalytic performance of metal oxides for the synthesis of propylene carbonate from urea and 1,2-propanediol

The influences of acid–base properties of metal oxides on the catalytic performance for synthesis of propylene carbonate from urea and 1,2-propanediol was investigated, and the reaction was stepwise. The amphoteric ZnO showed the best activity, and the yield of propylene carbonate reached 98.9%. The urea decomposition over oxides was characterized by using FTIR. ZnO, CaO, MgO and La₂O₃ were favorable to promote urea decomposition to form the isocyanate species, and the formation of isocyanate species was the key to urea alcoholysis. The catalytic activity of urea decomposition was consistency to the catalytic performance for synthesis of propylene carbonate. Based on these, the probable reaction mechanism was proposed.     

Access to Hydroxy-Functionalized Polypropylene through Coordination Polymerization

Preparation of polyethylenes containing hydroxy groups has been already industrialized through radical copolymerization under harsh conditions followed by alcoholysis. By contrast, hydroxy-functionalized polypropylene has proven a rather challenging goal in polymer science. Propylene can't be polymerized through a radical mechanism, and its coordination copolymerization with polar monomers is frustrated by catalyst poisoning. Herein, we report a new strategy to reach this target. The coordination polymerization of allenes by rare-earth-metal precursors affords pure 1,2-regulated polyallenes, which are facilely transformed into poly(allyl alcohol) analogues by subsequent hydroboration/oxidation. Strikingly, the copolymerization of allenes and propylene gives unprecedented hydroxy-functionalized polypropylene after post-polymerization modification. Mechanistic elucidation by DFT simulation suggests kinetic rather than thermodynamic control.     

Access to Hydroxy‐Functionalized Polypropylene through Coordination Polymerization

Preparation of polyethylenes containing hydroxy groups has been already industrialized through radical copolymerization under harsh conditions followed by alcoholysis. By contrast, hydroxy‐functionalized polypropylene has proven a rather challenging goal in polymer science. Propylene can't be polymerized through a radical mechanism, and its coordination copolymerization with polar monomers is frustrated by catalyst poisoning. Herein, we report a new strategy to reach this target. The coordination polymerization of allenes by rare‐earth‐metal precursors affords pure 1,2‐regulated polyallenes, which are facilely transformed into poly(allyl alcohol) analogues by subsequent hydroboration/oxidation. Strikingly, the copolymerization of allenes and propylene gives unprecedented hydroxy‐functionalized polypropylene after post‐polymerization modification. Mechanistic elucidation by DFT simulation suggests kinetic rather than thermodynamic control.     

Reaction of phenyldichlorophosphine with diacetyl

Conclusions Phenyldichlorophosphine reacts with diacetyl to form 5-methyl-2-phenyl-4-chloro-2-oxo-1,2-oxaphosphol-4-ene. Hydrolysis of this compound gives phenyl-(-chloro--oxo)butylphosphinic acid, and alcoholysis gives the ester of this acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 466–468, February, 1969.     

Investigation of the catalytic activity of an electron-deficient vanadium(IV) tetraphenylporphyrin: A new, highly efficient and reusable catalyst for ring-opening of epoxides

In this work, the catalytic activity of high-valent tetraphenylporphyrinatovanadium(IV) trifluoromethanesulfonate, [V^IV(TPP)(OTf)₂], in the nucleophilic ring-opening of epoxides is reported. This new V(IV) catalyst was used as an efficient catalyst for alcoholysis with primary (methanol, ethanol and n-propanol), secondary (iso-propanol) and tertiary alcohols (tert-butanol), hydrolysis and acetolysis of epoxides with acetic acid and also for the conversion of epoxides to 1,2-diacetates with acetic anhydride, conversion of epoxides to thiiranes with ammonium thiocyanate and thiourea, and for conversion of epoxides to acetonides with acetone. The catalyst was reused several times without loss of its activity.     

1，3，4，6－四硫代戊搭烯－2，5－二酮制备含硫取代基的四硫富瓦烯的研究

以１，３，４，６－四硫代戊搭烯－２，５－二酮为原料，经偶联、醇解、烃化或醇解、烃化、偶联等步骤，制得四甲硫基四硫富瓦烯、四乙硫基四硫富瓦烃、二喹喔啉硫醚、４－甲硫基－５－甲氧甲酰硫基－１，３－二硫环戊烯－２－酮、四甲硫基乙烯和４，４＇－二甲硫基－５，５＇－二甲氧甲酰硫基四硫富瓦烯及它的异构体混合物．提出了１，３，４，６－四硫代戊搭烯－２，５－二酮醇解机理．讨论了未得到某些预期产物的原因．报道了３种四硫富瓦烯衍生物的循环伏安图及电化学性质．     

Highly atom efficient catalytic reactions utilizing water and alcohols as reagents

In this accounts, we describe our recent studies on hydrolysis, alcoholysis, and addition of alcohols to organic molecules. The reactions utilizing water and alcohols as a reagent are one of the most basic and simple reactions. The palladium-catalyzed asymmetric hydrolysis and alcoholysis of vinyl ethers gave valuable axially chiral 1,1′-bi-2-naphthol and 1,1′-bi-2-phenol derivatives and chiral P-chirogenic compounds in optically active form. The reaction is applied for hydrolytic deallylation of N-allyl amide and allyl esters. The later one was achieved by palladium/ruthenium dual catalysts which is the first example of catalytic irreversible ester hydrolysis. Gold complexes also catalyzed vinyl ether alcoholysis and hydroalkoxylation of olefins. In the later reaction, simple unactivated olefins can be used as substrates and gave the product in 92% yield. The copper-DTBM-SEGPHOS complex catalyzed alcoholysis of azlactones which is the first example showing zero-order kinetic resolution.     

乙二醇醇解松木屑反应特征及机理分析

利用酸化的乙二醇作溶剂对松木屑进行醇解,探讨了温度和时间对醇解转化率的影响。利用热重分析、红外光谱分析、扫描电镜及X射线衍射考察了醇解残渣的性质。分别利用傅里叶变换红外光谱及色质联用分析了正己烷不溶物和可溶物中组分的分布及特征。结果表明,松木屑转化率在90 min、160℃达到最大值95.3%。松木屑中纤维素无定形区的组分和木质素发生了解离,醇解残渣的表面结构被破坏;正己烷不溶物是含有羟基、甲氧基及醚键等含氧官能团的化合物;正己烷可溶物主要由苯二甲酸酯、硬脂酸甲酯、2-甲基己酸丙酯、2-甲基丙酸、聚乙二醇及未反应的乙二醇组成。乙二醇与松木屑解离的羧酸发生酯化反应,对液相产物具有稳定作用,促进了松木屑的醇解反应;醇解过程中乙二醇自缩聚生成聚乙二醇,增大了乙二醇的消耗。     

Synthesiss of novel 3‐(2‐thienyl)‐1,2‐diazepino[3,4‐b]quinoxalines with algicidal activity

The reaction of the quinoxaline N‐oxide 1 with thiophene‐2‐carbaldehyde gave 6‐chloro‐2‐[1‐methyl‐2‐(2‐thienylmethylene)hydrazino]quinoxaline 4‐oxide 5 , whose reaction with 2‐chloroacrylonitrile afforded 8‐chloro‐2,3‐dihydro‐4‐hydroxy‐1‐methyl‐3‐(2‐thienyl)‐1H‐1,2‐diazepino[3,4‐b]quinoxaline‐5‐carbonitrile 6 . The reaction of compound 6 with various alcohols in the presence of a base effected alcoholysis to provide the 5‐alkoxy‐8‐chloro‐2,3,4,6‐tetrahydro‐1‐methyl‐4‐oxo‐3‐(2‐thienyl)‐1H‐1,2‐diazepino[3,4‐b]‐quinoxalines 7a‐d . The reaction of compounds 7a and 7b with diethyl azodicarboxylate effected dehydrogenation to give the 5‐alkoxy‐8‐chloro‐4,6‐dihydro‐1‐methyl‐4‐oxo‐3‐(2‐thienyl)‐1H‐1,2‐diazepino[3,4‐b]‐quinoxalines 8a and 8b , respectively. Compounds 8a and 8b were found to show good algicidal activities against Selenastrum capricornutum and Nitzchia closterium.     

Reactions of pyridinium and isoquinolinium phenacylides with nucleophiles

The hydrolysis, alcoholysis, and hydrazinolysis of N-phenacylpyridinium bromide lead to the corresponding benzoic acid derivatives. In addition, 3,6-diphenylpyridazine is formed during hydrazinolysis. The hydrolysis and alcoholysis of N-phenacylisoquinolinium bromide lead to its dimerization, whereas hydrazinolysis gives a triazinoisoquinoline derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 372–374, March, 1976.     

Theoretical Studies of Water''s and Methanol''s Effects on Alcoholysis of N-Benzyl-3-oxo-β-sultam

The mechanisms about the water's and methanol's effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density functional theory at the B3LYP/6-31G* level. The results, in comparison with a previous study on the relative reaction without the assistance of water and methanol, show that the added water or methanol can remarkably reduce the energy barrier of alcoholysis reaction of N-benzyl-3-oxo-β-sultam and the most favorite pathway is the breaking of C-N bond instead of S-N. It is also found that the reaction energy barrier of methanol-assisted alcoholysis is a little higher than that of the water-assisted one.