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Multi-enzymatic cascade reactions with Escherichia coli-based modules for synthesizing various bioplastic monomers from fatty acid methyl esters?
Multi-enzymatic cascade reaction systems were designed to generate biopolymer monomers using Escherichia coli-based cell modules, capable of carrying out one-pot reactions. Three cell-based modules, including a ω-hydroxylation module (Cell-Hm) to convert fatty acid methyl esters (FAMEs) to ω-hydroxy fatty acids (ω-HFAs), an amination module (Cell-Am) to convert terminal alcohol groups of the substrate to amine groups, and a reduction module (Cell-Rm) to convert the carboxyl groups of fatty acids to alcohol groups, were constructed. The product-oriented assembly of these cell modules involving multi-enzymatic cascade reactions generated ω-ADAs (up to 46 mM), α,ω-diols (up to 29 mM), ω-amino alcohols (up to 29 mM) and α,ω-diamines (up to 21 mM) from 100 mM corresponding FAME substrates with varying carbon chain length (C8, C10, and C12). Finally 12-ADA and 1,12-diol were purified with isolated yields of 66.5% and 52.5%, respectively. The multi-enzymatic cascade reactions reported herein present an elegant ‘greener’ alternative for the biosynthesis of various biopolymer monomers from renewable saturated fatty acids.
Jung, Hyunsang,Kim, Byung-Gee,Kim, Ye Chan,Park, Beom Gi,Patil, Mahesh D.,Sarak, Sharad,Yoo, Hee-Wang,Yun, Hyungdon
supporting information
p. 2222 - 2231
(2022/04/03)

Depolymerization of Hydroxylated Polymers via Light-Driven C-C Bond Cleavage
The accumulation of persistent plastic waste in the environment is widely recognized as an ecological crisis. New chemical technologies are necessary both to recycle existing plastic waste streams into high-value chemical feedstocks and to develop next-generation materials that are degradable by design. Here, we report a catalytic methodology for the depolymerization of a commercial phenoxy resin and high molecular weight hydroxylated polyolefin derivatives upon visible light irradiation near ambient temperature. Proton-coupled electron transfer (PCET) activation of hydroxyl groups periodically spaced along the polymer backbone furnishes reactive alkoxy radicals that promote chain fragmentation through C-C bond β-scission. The depolymerization produces well-defined and isolable product mixtures that are readily diversified to polycondensation monomers. In addition to controlling depolymerization, the hydroxyl group modulates the thermomechanical properties of these polyolefin derivatives, yielding materials with diverse properties. These results demonstrate a new approach to polymer recycling based on light-driven C-C bond cleavage that has the potential to establish new links within a circular polymer economy and influence the development of new degradable-by-design polyolefin materials.
Nguyen, Suong T.,McLoughlin, Elizabeth A.,Cox, James H.,Fors, Brett P.,Knowles, Robert R.
supporting information
p. 12268 - 12277
(2021/08/23)

Erbium-Catalyzed Regioselective Isomerization-Cobalt-Catalyzed Transfer Hydrogenation Sequence for the Synthesis of Anti-Markovnikov Alcohols from Epoxides under Mild Conditions
Herein, we report an efficient isomerization-transfer hydrogenation reaction sequence based on a cobalt pincer catalyst (1 mol %), which allows the synthesis of a series of anti-Markovnikov alcohols from terminal and internal epoxides under mild reaction conditions (≤55 °C, 8 h) at low catalyst loading. The reaction proceeds by Lewis acid (3 mol % Er(OTf)3)-catalyzed epoxide isomerization and subsequent cobalt-catalyzed transfer hydrogenation using ammonia borane as the hydrogen source. The general applicability of this methodology is highlighted by the synthesis of 43 alcohols from epoxides. A variety of terminal (23 examples) and 1,2-disubstituted internal epoxides (14 examples) bearing different functional groups are converted to the desired anti-Markovnikov alcohols in excellent selectivity and yields of up to 98%. For selected examples, it is shown that the reaction can be performed on a preparative scale up to 50 mmol. Notably, the isomerization step proceeds via the most stable carbocation. Thus, the regiochemistry is controlled by stereoelectronic effects. As a result, in some cases, rearrangement of the carbon framework is observed when tri-and tetra-substituted epoxides (6 examples) are converted. A variety of functional groups are tolerated under the reaction conditions even though aldehydes and ketones are also reduced to the respective alcohols under the reaction conditions. Mechanistic studies and control experiments were used to investigate the role of the Lewis acid in the reaction. Besides acting as the catalyst for the epoxide isomerization, the Lewis acid was found to facilitate the dehydrogenation of the hydrogen donor, which enhances the rate of the transfer hydrogenation step. These experiments additionally indicate the direct transfer of hydrogen from the amine borane in the reduction step.
Liu, Xin,Longwitz, Lars,Spiegelberg, Brian,T?njes, Jan,Beweries, Torsten,Werner, Thomas
p. 13659 - 13667
(2020/11/30)

One-pot biosynthesis of 1,6-hexanediol from cyclohexane by: De novo designed cascade biocatalysis
1,6-Hexanediol (HDO) is an important precursor in the polymer industry. The current industrial route to produce HDO involves energy intensive and hazardous multistage (four-pot-four-step) chemical reactions using cyclohexane (CH) as the starting material, which leads to serious environmental problems. Here, we report the development of a biocatalytic cascade process for the biotransformation of CH to HDO under mild conditions in a one-pot-one-step manner. This cascade biocatalysis operates by using a microbial consortium composed of three E. coli cell modules, each containing the necessary enzymes. The cell modules with assigned functions were engineered in parallel, followed by combination to construct E. coli consortia for use in biotransformations. The engineered E. coli consortia, which contained the corresponding cell modules, efficiently converted not only CH or cyclohexanol to HDO, but also other cycloalkanes or cycloalkanols to related dihydric alcohols. In conclusion, the newly developed biocatalytic process provides a promising alternative to the current industrial process for manufacturing HDO and related dihydric alcohols. This journal is
Kang, Lixin,Li, Aitao,Li, Qian,Li, Renjie,Wang, Fei,Yu, Xiaojuan,Zhang, Zhongwei,Zhao, Jing
p. 7476 - 7483
(2020/11/23)

Robust cobalt oxide catalysts for controllable hydrogenation of carboxylic acids to alcohols
The selective catalytic hydrogenation of carboxylic acids is an important process for alcohol production, while efficient heterogeneous catalyst systems are still being explored. Here, we report the selective hydrogenation of carboxylic acids using earth-abundant cobalt oxides through a reaction-controlled catalysis process. The further reaction of the alcohols is completely hindered by the presence of carboxylic acids in the reaction system. The partial reduction of cobalt oxides by hydrogen at designated temperatures can dramatically enhance the catalytic activity of pristine samples. A wide range of carboxylic acids with a variety of functional groups can be converted to the corresponding alcohols at a yield level applicable to large-scale production. Cobalt monoxide was established as the preferred active phase for the selective hydrogenation of carboxylic acids.
Song, Song,Wang, Dong,Di, Lu,Wang, Chuanming,Dai, Weili,Wu, Guangjun,Guan, Naijia,Li, Landong
p. 250 - 257
(2018/02/20)

Hydrogenation of dicarboxylic acids to diols over Re-Pd catalysts
A Re-Pd/SiO2 (Re/Pd = 8) catalyst was applied to hydrogenation of dicarboxylic acids (succinic acid, glutaric acid and adipic acid) to diols. In the hydrogenation of dicarboxylic acids, ex situ liquid-phase (in only 1,4-dioxane solvent) reduced Re-Pd/SiO2 showed much higher activity than in situ liquid-phase (in the mixture of dicarboxylic acid and 1,4-dioxane) and gas-phase reduced ones, in which the in situ liquid-phase reduced catalyst has been reported to show good activity in the hydrogenation of monocarboxylic acids. High diol yields (71-89%) were achieved in the hydrogenation of dicarboxylic acids on the ex situ liquid-phase reduced catalyst at 413 K. Lactones and hydroxycarboxylic acids were first formed as intermediates in the reaction of C4-C5 and ≥C6 dicarboxylic acids, respectively. Characterization using XRD, XPS and XAS indicates that ex situ liquid-phase reduced catalysts with high activity contains comparable amounts of Re0 and Ren+ species, both of which have been reported to be necessary for good performance. The amount of Ren+ species on the in situ liquid-phase reduced catalysts is much larger than that of surface Re0 species. This result suggests that the presence of dicarboxylic acids suppresses the reduction of Re species to Re0 on the calcined catalysts while that of monocarboxylic acids does not, which leads to the low activity in the hydrogenation of dicarboxylic acids on in situ liquid-phase reduced catalysts.
Takeda, Yasuyuki,Tamura, Masazumi,Nakagawa, Yoshinao,Okumura, Kazu,Tomishige, Keiichi
p. 5668 - 5683
(2016/07/21)

PROCESS FOR THE MANUFACTURE OF A SATURATED ALCOHOL
The present invention relates to a process for the manufacture of a saturated primary alcohol from an unsaturated aliphatic ester comprising the steps of: a) Providing an aliphatic ester having at least one carbon-carbon double bond; b) Carrying out a metathesis of said ester in the presence of a ruthenium carbenebased catalyst thereby obtaining a first reaction mixture; c) Adding a ligand and a base to the first reaction mixture, wherein the ligand comprises at least one donor atom chosen from the group consisting of a nitrogen atom and a phosphorus atom thereby obtaining a second reaction mixture comprising an ester product resulting from the metathesis reaction ; d) Carrying out a homogeneous hydrogenation of the ester-product resulting from the metathesis, thereby obtaining a saturated primary alcohol. Further, the present invention relates to a catalyst for the hydrogenation of esters and to a process for the hydrogenation of esters using said catalyst.
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(2015/11/11)

ACYCLIC ALKENES VIA OZONOLYSIS OF MULTI-UNSATURATED CYCLOALKENES
A method of making a compound of formula (IIa) by selective ozonolysis of a compound of formula (I) is provided, wherein A is a C6-C10 alkene chain with at least one double bond, R1 is a C1-C10 alkyl, and R3 is an oxygen-containing functional group.
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Paragraph 00156

(2015/02/02)

A highly active and air-stable ruthenium complex for the ambient temperature anti-markovnikov reductive hydration of terminal alkynes
The conversion of terminal alkynes to functionalized products by the direct addition of heteroatom-based nucleophiles is an important aim in catalysis. We report the design, synthesis, and mechanistic studies of the half-sandwich ruthenium complex 12, which is a highly active catalyst for the anti-Markovnikov reductive hydration of alkynes. The key design element of 12 involves a tridentate nitrogen-based ligand that contains a hemilabile 3-(dimethylamino) propyl substituent. Under neutral conditions, the dimethylamino substituent coordinates to the ruthenium center to generate an air-stable, 18-electron, κ3-complex. Mechanistic studies show that the dimethylamino substituent is partially dissociated from the ruthenium center (by protonation) in the reaction media, thereby generating a vacant coordination site for catalysis. These studies also show that this substituent increases hydrogenation activity by promoting activation of the reductant. At least three catalytic cycles, involving the decarboxylation of formic acid, hydration of the alkyne, and hydrogenation of the intermediate aldehyde, operate concurrently in reactions mediated by 12. A wide array of terminal alkynes are efficiently processed to linear alcohols using as little as 2 mol % of 12 at ambient temperature, and the complex 12 is stable for at least two weeks under air. The studies outlined herein establish 12 as the most active and practical catalyst for anti-Markovnikov reductive hydration discovered to date, define the structural parameters of 12 underlying its activity and stability, and delineate design strategies for synthesis of other multifunctional catalysts.
Zeng, Mingshuo,Li, Le,Herzon, Seth B.
supporting information
p. 7058 - 7067
(2014/06/09)

Regioselective reductive hydration of alkynes to form branched or linear alcohols
The regioselective reductive hydration of terminal alkynes using two complementary dual catalytic systems is described. Branched or linear alcohols are obtained in 75-96% yield with ?25:1 regioselectivity from the same starting materials. The method is compatible with terminal, di-, and trisubstituted alkenes. This reductive hydration constitutes a strategic surrogate to alkene oxyfunctionalization and may be of utility in multistep settings.
Li, Le,Herzon, Seth B.
supporting information
p. 17376 - 17379,4
(2020/09/16)

Elaboration of the ether cleaving ability and selectivity of the classical Pearlman's catalyst [Pd(OH)2/C]: Concise synthesis of a precursor for a myo-inositol pyrophosphate
The cleavage of propargyl, allyl, benzyl, and PMB ethers by Pd(OH) 2/C can be tuned in that order, by varying the reaction conditions. Other moieties such as C-C double bonds, esters, trityl ether, p-bromo and p-nitrobenzyl ethers are stable to these reaction conditions. Cleavage of allyl ethers can be made catalytic by using 1:1 mixture of Pd(OH)2/C and Pd/C. The synthetic potential of the selective ether cleaving ability of Pd(OH)2/C, essentially under neutral conditions, has been demonstrated by an efficient synthesis of a precursor for the preparation of an inositol pyrophosphate derivative.
Mart, Alson,Shashidhar, Mysore S.
p. 9769 - 9776,8
(2012/12/11)

Elaboration of the ether cleaving ability and selectivity of the classical Pearlman's catalyst [Pd(OH)2/C]: Concise synthesis of a precursor for a myo-inositol pyrophosphate
The cleavage of propargyl, allyl, benzyl, and PMB ethers by Pd(OH) 2/C can be tuned in that order, by varying the reaction conditions. Other moieties such as C-C double bonds, esters, trityl ether, p-bromo and p-nitrobenzyl ethers are stable to these reaction conditions. Cleavage of allyl ethers can be made catalytic by using 1:1 mixture of Pd(OH)2/C and Pd/C. The synthetic potential of the selective ether cleaving ability of Pd(OH)2/C, essentially under neutral conditions, has been demonstrated by an efficient synthesis of a precursor for the preparation of an inositol pyrophosphate derivative.
Mart, Alson,Shashidhar, Mysore S.
p. 9769 - 9776
(2013/01/13)

METHOD FOR PRODUCING ALCOHOL COMPOUND
Provided is a method for producing an alcohol compound, which enables the alcohol compound to be obtained at a high yield from an amide compound or amine compound. The method for producing an alcohol compound, which is characterized by comprising allowing an alcohol in a supercritical state to act on the amide compound or amine compound in the presence of a carboxylic acid derivative to obtain the alcohol compound.
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(2012/06/18)

Bacterial CYP153A monooxygenases for the synthesis of omega-hydroxylated fatty acids
CYP153A from Marinobacter aquaeolei has been identified as a fatty acid ω-hydroxylase with a broad substrate range. Two hotspots predicted to influence substrate specificity and selectivity were exchanged. Mutant G307A is 2- to 20-fold more active towards fatty acids than the wild-type. Residue L354 is determinant for the enzyme ω-regioselectivity.
Honda Malca, Sumire,Scheps, Daniel,Kuehnel, Lisa,Venegas-Venegas, Elena,Seifert, Alexander,Nestl, Bettina M.,Hauer, Bernhard
supporting information; experimental part
p. 5115 - 5117
(2012/06/30)

Regioselective ω-hydroxylation of medium-chain n-alkanes and primary alcohols by CYP153 enzymes from Mycobacterium marinum and Polaromonas sp. strain JS666
The oxofunctionalization of saturated hydrocarbons is an important goal in basic and applied chemistry. Biocatalysts like cytochrome P450 enzymes can introduce oxygen into a wide variety of molecules in a very selective manner, which can be used for the synthesis of fine and bulk chemicals. Cytochrome P450 enzymes from the CYP153A subfamily have been described as alkane hydroxylases with high terminal regioselectivity. Here we report the product yields resulting from C5-C12 alkane and alcohol oxidation catalyzed by CYP153A enzymes from Mycobacterium marinum (CYP153A16) and Polaromonas sp. (CYP153A P. sp.). For all reactions, byproduct formation is described in detail. Following cloning and expression in Escherichia coli, the activity of the purified monooxygenases was reconstituted with putidaredoxin (CamA) and putidaredoxin reductase (CamB). Although both enzyme systems yielded primary alcohols and α,ω-alkanediols, each one displayed a different oxidation pattern towards alkanes. For CYP153A P. sp. a predominant ω-hydroxylation activity was observed, while CYP153A16 possessed the ability to catalyze both ω-hydroxylation and α,ω- dihydroxylation reactions.
Scheps, Daniel,Honda Malca, Sumire,Hoffmann, Helen,Nestl, Bettina M.,Hauer, Bernhard
scheme or table
p. 6727 - 6733
(2011/11/30)

Extracts of Isochrysis sp.
The present invention relates to extracts of Isochrysis sp., preferably Tahitian Isochrysis, its cosmetic, dermatological and/or therapeutic uses and compositions and cosmetic, dermatological or therapeutic products comprising such an extract of Isochrysis sp., preferably Tahitian Isochrysis.
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(2010/04/25)

Extracts of isochrysis sp.
The present invention relates to extracts of Isochrysis sp., preferably Tahitian Isochrysis, its cosmetic, dermatological and/or therapeutic uses and compositions and cosmetic, dermatological or therapeutic products comprising such an extract of Isochrysis sp., preferably Tahitian Isochrysis.
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(2010/04/25)

EXTRACTS OF TETRASELMIS SP.
The present invention relates to extracts of Tetraselmis sp., preferably Tetraselmis suecica, its cosmetic, dermatological and/or therapeutic uses and compositions and cosmetic, dermatological or therapeutic products comprising such an extract of Tetraselmis sp., preferably Tetraselmis suecica.
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(2010/06/19)

Extracts of Tetraselmis sp. for cosmetic and therapeutic purposes
The present invention relates to extracts of Tetraselmis sp., preferably Tetraselmis suecica, its cosmetic, dermatological and/or therapeutic uses and compositions and cosmetic, dermatological or therapeutic products comprising such an extract of Tetraselmis sp., preferably Tetraselmis suecica.
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(2010/06/20)

Comparison of two vectors for functional expression of a bacterial cytochrome P450 gene in escherichia coli using CYP153 genes
Two vectors, pTTNScamAB and pRED, have been used for the functional expression of bacterial class I cytochrome P450 (P450) genes in Escherichia coli, which utilize putidaredoxin reductase (CamA) and putidar-edoxin (CamB), and the reductase domain of a self-sufficient P450RhF respectively, for electron transfer from NAD(P)H to a P450 protein. We here compared the efficiency of bioconversion with the two vectors towards n-octane, cyclohexane, n-butylbenzene, and 2-n-butylbenzofuran using two well-characterized CYP153A genes, aciA and CYP153A13a (P450balk). As for n-octane bioconversion, aciA and pT7camAB was the best combination for the production of 1-octanol and 1,8-octanediol. As for the bioconversion of cyclohexane, n-butylbenzene and 2-n-butylbenzofuran, CYP153A13a with pRED achieved the most efficient bioconversion, as compared by conversion ratio per active CYP153A protein content. It was also found that 2-n-butylbenzofuran is biotransformed into 4-benzofuran-2-yl-butyric acid via 4-benzofuran-2-yl-butan-l-ol with E. coli cells expressing CYP153A.
Fujita, Naoya,Sumisa, Futoshi,Shindo, Kazutoshi,Kabumoto, Hiroki,Arisawa, Akira,Ikenaga, Hiroshi,Misawa, Norihiko
experimental part
p. 1825 - 1830
(2010/03/24)

Novel Method for Preparing Unsaturated Fatty Hydroxyacids
The invention concerns a method for preparing a compound of formula (I), wherein: R3 and R1 represent in particular H and n is greater than 4, said preparation method including performing a Wittig-Horner reaction with a phosphonate on a lactol, so as to obtain a hydroxyester and, optionally a saponification reaction of said hydroxyester.
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(2008/12/08)

Magnetically separable Pd catalyst for highly selective epoxide hydrogenolysis under mild conditions
A magnetically separable palladium catalyst was synthesized simply through a sol-gel process incorporating palladium nanoparticles and superparamagnetic iron oxide nanoparticles in aluminum oxyhydroxide matrix, which is highly active and selective for epoxide hydrogenolysis at room temperature under 1 atm H 2. The catalyst was recycled for 25 times without loss of the activity.
Kwon, Min Serk,Park, In Soo,Jang, Jum Suk,Lee, Jae Sung,Park, Jaiwook
p. 3417 - 3419
(2008/02/12)

Iterative tandem catalysis of secondary diols and diesters to chiral polyesters
The well-known dynamic kinetic resolution of secondary alcohols and esters was extended to secondary diols and diesters to afford chiral polyesters. This process is an example of iterative tandem catalysis (ITC), a polymerization method where the concurrent action of two fundamentally different catalysts is required to achieve chain growth. In order to procure chiral polyesters of high enantiomeric excess value (ee) and good molecular weight, the catalysts employed need to be complementary and compatible during the polymerization reaction. We here show that Shvo's catalyst and Novozym 435 fulfil these requirements. The optimal polymerization conditions of 1,1′-(1,3-phenylene) diethanol (1,3-diol) and diisopropyl adipate required 2mol% Shvo's catalyst and 12 mg Novozym 435 per mmol alcohol group in the presence of 0.5 M 2,4-dimethyl-3- pentanol as the hydrogen donor. With these conditions, chiral polyesters were obtained with peak molecular weights up to 15kDa, an ee value up to 99% and with 1-3% ketone end groups. Also with the structural isomer, 1,4-diol, a chiral polyester was obtained, albeit with lower molecular weight (8.3 kDa) and slightly lower ee (94%). Aliphatic secondary diols also resulted in enantio-enriched polymers but at most an ee of 46% was obtained with molecular weights in the range of 3.33.7 kDa. This low ee originates from the intrinsic low enantioselectivity of Novozym 435 for this type of secondary aliphatic diols. The results presented here show that ITC can be applied to procure chiral polyesters with good molecular weight and high ee from optically inactive AA-BB type monomers.
Van As, Bart A.C.,Van Buijtenen, Jeroen,Mes, Tristan,Palmans, Anja R.A.,Meijer
p. 8325 - 8332
(2008/09/16)

Method for the preparation of unsaturated hydroxy fatty acids and their esters, their use in pharmaceutical and/or cosmetic preparations
A method of preparing unsaturated hydroxy fatty acids and esters thereof corresponding to general formula (Id): wherein n=1 to 4, m=2 to 16, R1═OH, Cl, Br, OR3 in which R3 is a straight or branched alkyl, alkenyl or alkynyl radical of 1 to 16 carbons or glycerol esters, optionally substituted by one or more atoms selected from the group consisting of carbon, nitrogen, sulfur and halogens, R2═H, SiR′1R′2R′3 in which R′1, R′2 and R′3 can be identical or different from each other and are a straight or branched alkyl, alkenyl or alkynyl radical of 1 to 16 carbons or glycerol esters, optionally substituted by one or more atoms selected from the group consisting of carbon, nitrogen, sulfur and halogens, or R2═C—Ar3 with Ar representing an aryl radical optionally substituted by one or more atoms selected from the group consisting of carbon, nitrogen, sulfur and halogens, or R2=the tetrahydropyranyl of formula: is disclosed.
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Page 5

(2010/02/08)

The head-to-head reductive coupling of homoallylic alcohols promoted by titanium(II)-olefin complexes
Reaction of homoallylic alcohols 1a-e with i-PrMgBr in the presence of Ti(i-PrO)4 leads to the unbranched saturated diols 2a-e as the main products in moderate to good yields. The head-to-head regioselectivity in reductive coupling of 4-penten-
Isakov, Vladimir E.,Kulinkovich, Oleg G.
p. 967 - 970
(2007/10/03)

DERMATOLOGICAL COMPOSITIONS AND METHODS
Disclosed are methods and compositions for regulating the melanin content of mammalian melanocytes; regulating pigmentation in mammalian skin, hair, wool or fur; treating or preventing various skin and proliferative disorders; by administration of various compounds, including alcohols, diols and/or triols and their analogues.
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(2008/06/13)

New reactivity of functionalised organolithium compounds in the presence of Cu(I) or Cu(II) salts: Conjugate addition, acylation or dimerisation
The reaction of functionalised organolithium compounds 1 with electrophilic olefins 2 in the presence of copper(I) iodide and HMPA in THF at -78°C leads, after hydrolysis with a saturated solution of ammonium chloride, to the corresponding products 3 resulting from a conjugate addition. The same process but using an acyl chloride instead of the electrophilic olefins affords the expected ketone 4 from an acylation process. Finally, when intermediates 1 are treated with copper(II) chloride in THF at -78°C, the corresponding dimers 5 are isolated after the same hydrolytic treatment.
Pastor, Isidro M,Yus, Miguel
p. 2371 - 2378
(2007/10/03)

A highly efficient, mild, and selective cleavage of beta-methoxyethoxymethyl (MEM) ethers by cerium(III) chloride in acetonitrile.
[structure: see text]. A highly selective cleavage of MEM ethers has been achieved in high yields using CeCl3.7H2O in refluxing acetonitrile under mild and neutral reaction conditions. The method is very rapid and compatible with other hydroxyl protecting groups such as Bn, TBDPS, Ac, Me, Tr, PMB, benzylidene, THP, MOM, BOM, and NHAc present in the substrate.
Sabitha,Babu,Rajkumar,Srividya,Yadav
p. 1149 - 1151
(2007/10/03)

A novel hydrogen transfer hydroalumination of alkenes with triisobutylaluminum catalyzed by Pd and other late transition metal complexes
Hydrogen transfer hydroalumination of terminal alkenes and dienes can be achieved with 1.1 equiv. of (i-Bu)3Al and catalytic amounts of Cl2Pd(PPh3)2 and other late transition metal complexes containing Co, Rh, Ni, and Pt at ambient temperature in high yields.
Gagneur, Sebastien,Makabe, Hidefumi,Negishi, Ei-Ichi
p. 785 - 787
(2007/10/03)

Cation exchange resin supported oxidation of alkylbenzenes and olefins using potassium permanganate
Rapid and efficient oxidation of alkylbenzene side chains at the benzylic positions as well as oxidative cleavage of olefins with potassium permanganate in presence of solid polymeric cation exchange resins in good yields is reported.
Joshi, Padmaker L.,Hazra, Braja G.
p. 38 - 39
(2007/10/03)

Copper(I) or (II)-mediated conjugate addition or dimerisation of functionalised organolithium compounds
The reaction of different functionalised organolithium intermediates 1- 3 with several electrophilic olefins 6 (2-cyclopentenone, 2-cyclohexenone, methyl vinyl ketone, benzylideneacetone, benzylideneacetophenone and ethyl acrylate) in the presence of copper(I) salts (bromide and iodide) in THF at -78°C gives, after hydrolysis with ammonium chloride, the expected products resulting from a conjugate addition. In the presence of copper(II) chloride intermediates 1-5 undergo dimerisation to yield the expected dimers. (C) 2000 Elsevier Science Ltd.
Pastor, Isidro M.,Yus, Miguel
p. 1589 - 1592
(2007/10/03)

Treatment of neurodegenerative diseases
Disclosed are methods for increasing the differentiation of mammalian neuronal cells for purposes of treating neurodegenerative diseases or nerve damage by administration of various compounds including alcohols, diols and/or triols and their analogues.
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(2008/06/13)

An efficient and selective deprotection of tetrahydropyranyl ethers by CeCl3.7H2O
Treatment of tetrahydropyranyl ethers with cerium (III) chloride heptahydrate in methanol provides a simple, convenient and selective method for detetrahydropyranylation, and the parent alcohols are obtained in high yields.
Reddy,Neelakantan,Iyengar
p. 4107 - 4111
(2007/10/03)

Treatment of diseases mediated by the nitric oxide/cGMP/protein kinase G pathway
Disclosed are methods and compositions for stimulating cellular nitric oxide (NO) synthesis, cyclic guanosine monophosphate levels (cGMP), and protein kinase G (PKG) activity for purposes of treating diseases mediated by deficiencies in the NO/cGMP/PKG signal transduction pathway, by administration of various compounds including alcohols, diols and/or triols and their analogues.
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(2008/06/13)

Stannous chloride catalyzed deprotection of tetrahydropyranyl ethers
An efficient and mild methodology for the deprotection of tetrahydropyranyl ethers using anhydrous stannous chloride in methanol is described.
Davis, K. Joju,Bhalerao,Rao, B. Vittal
p. 211 - 212
(2007/10/03)

Pheromones of insects and their analogs. LII. Sythesis of dodec-9-en-1-yl and tetradec-11-en-1-yl acetates from the products of the partial ozonolysis of cycloocta-1z,5z-diene and cyclodeca-1e,5z-diene
A new approach to the synthesis of octane-1,8-and decane-1,10-diols based on the partial ozonolysis of cyclic oligomers has been developed.
Odinokov,Botsman,Gladysheva
p. 381 - 383
(2007/10/03)

Preparation and Scope of a Remarkably Robust Primary Alcohol Protective Group
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Cho, Hyun-Sung,Yu, Jurong,Falck, J. R.
p. 8354 - 8355
(2007/10/02)

Unique Template Effects of Distannoxane Catalysts in Transesterification of Diol esters
1,n-Diol diacetates (n = 2,3,4) are selectively converted into the corresponding monoacetates by distannoxane-catalyzed transesterification.Such unique selectivity is not encountered with 1,n-diol diacetates where n>/=5.A great difference in reactivity is also seen in the transesterification between methyl butyrate and 1,n-diol monoacetates: the ethylene glycol derivative sluggishly undergoes transesterification whereas higher homologs react smoothly.The unique template effects of the catalysts are discussed in terms of cooperation of two different tin atoms which are located in the proximity.
Otera, Junzo,Dan-oh, Nobuhisa,Nozaki, Hitosi
p. 3065 - 3074
(2007/10/02)

Cosmetic composition
A water-pin-silicone oil emulsion, suitable for topical application to mammalian skin or hair, comprises, in addition to water, a volatile polydimethylsiloxane, a silicone surfactant ingredient comprising a polymer of dimethylpolysiloxane with polyoxyethylene and/or polyoxypropylene side chains having a molecular weight of from 10,000 to 50,000, a 2-hydroxyalkanoic acid or derivative thereof, ultrafine titanium dioxide, and an inorganic electrolyte.
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(2008/06/13)

Lanthanoids in Organic Synthesis. I. The Novel Reduction of Carboxylic Acids with Samarium Diiodide-Base System
Aromatic and aliphatic carboxylic acids were rapidly reduced with samarium diiodide by the addition of base in the presence of protic solvent at room temperature to the corresponding alcohols.Sodium benzoate was similarly reduced with samarium diiodide in the presence of H2O in a good yield.In the similar reactions of benzoic acid derivatives bearing carboxyl, formyl, carbamoyl, methoxyl, and chloro groups, these functional groups were also reduced to the corresponding alcohol or amine derivatives.Interestingly, the carboxyl and formyl groups of benzoic acids were partly reduced into the methyl group.
Kamochi, Yasuko,Kudo, Tadahiro
p. 3049 - 3054
(2007/10/02)

Lactones. 2. Enthalpies of hydrolysis, reduction, and formation of the C4-C13 monocyclic lactones. Strain energies and conformations
The enthalpies of hydrolysis of the monocyclic lactones from γ-butyrolactone to tridecanolactone were determined calorimetrically, and the acyclic ethyl having the number of atoms were studied in the fashion. The enthalpies of reduction of the lactones to the corresponding α,ω-alkanediols with lithium triethylborohydride also were determined. The enthalpies of formation of the lactones and the ethyl esters were derived from these data. They were converted to values for the gas phase by measuring the enthalpies of vaporization of ethyl esters and of lactones. In the of γ-butyrolactone and δ-valerolactone, the enthalpies of formation were in good accord with the previously reported values determined via combustion calorimetry. The strain energies of the lactones were obtained via isodesmic reactions. Valerolactone had a strain energy of 11 kcal/mol, and the largest strain energy was found with octanolactone (13 kcal/mol). The conformations of γ-butyrolactone and δ-valerolactone were studied via MP2/6-31G* geometry optimizations, and the conformations of the other lactones were studied with use of the molecular mechanics program MM3. The energies of the lactones estimated via molecular mechanics were compared with the experimental results.
Wiberg, Kenneth B.,Waldron, Roy F.
p. 7697 - 7705
(2007/10/02)

PHEROMONES OF INSECTS AND THEIR ANALOGS. XXVIII. PRACTICAL SYNTHESIS OF TETRADECA-9Z,12E-DIEN-1-YL ACETATE - A COMPONENT OF THE SEX PHEROMONES OF INSECTS OF THE ORDER LEPIDOPTERA
Tetradeca-9Z,12E-dien-1-yl acetate, a sex pheromone of the Indian meal moth Plodia interpunctella has been synthesized from the readily available product of the hydrodimerization of butadiene - octa-1,7-diene.
Odinokov, V. N.,Dzhemilev, U. M.,Ishumuratov, G. Yu.,Botsman, L. P.,Ibragimov, A. G.,et al.
p. 238 - 240
(2007/10/02)

Cosmetic composition
A water-in-silicone oil emulsion, suitable for topical application to mammalian skin or hair, comprises, in addition to water, a volatile polydimethylsiloxane, a silicone surfactant ingredient comprising a polymer of dimethylpolysiloxane with polyoxyethylene and/or polyoxypropylene side chains having a molecular weight of from 10,000 to 50,000, an inorganic electrolyte and preferably a 2-hydroxyalkanoic acid or derivative thereof, and an alkane diol.
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(2008/06/13)

SYNTHESIS OF THE SEX PHEROMONE OF THE GRAIN MOTH Ephestia Elutella
A most convenient synthesis of tetradeca-9Z,12E-dien-1-ol and its acetate - components of the sex pheromone of the grain moth - has been carried out on the basis of a scheme for obtaining a cis-1,trans-4-dienic system.
Kasymzhanova, M.,Abdukakharov, V. S.,Kamaev, F. G.,Abduvakhabov, A. A.
p. 708 - 713
(2007/10/02)

Ozonolysis of Tetrasubstituted Ethylenes, Cycloolefins, and Conjugated Dienes on Polyethylene
Ozonolyses of four tetrasubstituted ethylenes (7a-d), of two medium-sized cycloolefins (10a,b), and of norbornene (14) on polyethylene gave the corresponding ozonides, which could not be obtained by ozonolyses in solution.Ozonolyses of three conjugated dienes (25a,b,28) on polyethylene gave the corresponding diozonides, as the first examples of this class of ozonides.The thermal decomposition of some of the ozonides has been studied.
Griesbaum, Karl,Volpp, Willi,Greinert, Reinhard,Greunig, Hans-Joachim,Schmid, Jurgen,Henke, Henning
p. 383 - 389
(2007/10/02)

Symmetrical Alkoxysilyl Ethers. A New Class of Alcohol-Protecting Groups. Preparation of tert-Butoxydiphenylsilyl Ethers
The preparation and evaluation of a new class of alcohol-protecting groups, the alkoxydiphenylsilyl ethers, are described.In particular, tert-butoxydiphenylsilyl ethers, which can be formed from primary, secondary, or tertiary alcohols and tert-butoxydiphenylsilyl chloride, offer the useful synthetic properties of acid stability and high fluoride reactivity.Opportunities for selective silyl group cleavage are highlighted.
Gillard, John W.,Fortin, Rejean,Morton, Howard E.,Yoakim, Christiane,Quesnelle, Claude A.,at al.
p. 2602 - 2608
(2007/10/02)

SYNTHESIS OF PHEROMONES, III IMPROVED AND STEREOCONTROLLED SYNTHESES OF ISOMERIC MIXTURES OF 8-DODECEN-1-YL ACETATES
Simple syntheses have been developed for the preparation of isomeric mixtures of 8-dodecen-1-yl acetates, which are active sex pheromones of many insect species.The Wittig reaction under modified conditions and reduction of the C-C triple bond were applied for the stereocontrolled formation of the C-C double bond.
Vinczer, Peter,Juvanecz, Zoltan,Novak, Lajos,Szantay, Csaba
p. 737 - 748
(2007/10/02)

INSECT PHEROMONES AND THEIR ANALOGUES. XVI. PRACTICAL SYNTHESIS OF HEXADEC-9Z-ENAL - A COMPONENT OF THE SEX PHEROMONE OF THE COTTON BOLLWORM Heliothis armigera
A synthesis of hexadec-9Z-enal - a component of the sex pheromone of the cotton bollworm Heliothis armigera (Huebner) - based on cyclooctene (I) is proposed.Through a solution of 22 g of (I), 250 ml of cyclohexane, and 40 ml of MeOH is passed (at 5 deg C) 0.2 M O3/O2, the solution is decanted off, and the precipitated ozonide is dissolved in 200 ml of MeOH and is reduced with 19 g of NaBH4 (40 deg C) with the isolation, after the usual working up, of 23.4 g of octane-1,8-diol (II).From 0.5 mole of (II) and 0.6 mole of 45percent HBr 8-bromooctan-1-ol (III) is obtained and this is converted into 1-(2-(THPL)oxy)-8-bromooctane (IV).The condensation of (IV) with oct-1-yne (Ar, LiNH2, HMPTA, 10 deg C, 1 h, and then 55 deg C, 10 h) leads to 1-(2-THPL-oxy)hexadec-9-yne (V) the hydrolysis of which (MeOH, H2O, p-TsOH, 20 deg C for 20 h) yields hexadec-9-yn-ol (VI).The reduction of (VI) (Et2O, iso-BuMgBr, Cp2TiCl2, 0 deg C, 15 min, then 20 deg C, 1 h) yields hexadec-9Z-en-1-ol (VII).The oxidation of (VII) (PyHCrO3+ Cl-, CH2Cl2, 20 deg C, 2 h) gives hexadec-9Z-enal (VIII).Characteristics of the compounds (yield (percent), nD20(25): (II) - 80, mp 61-62 deg C; (III) - 75, 1.4807; (IV) - 99, -; (V) - 52, 1,4650; (VI) - 85, 1.4657; (VII) - 99, 1.4650; (VIII) - 98, 1.4600.Characteristics of the IR and PMR spectra of compounds (V-VII) are given.
Odinolov, V. N.,Dzhemilev, U. M.,Ishmuratov, G. Yu.,Botsman, L. P.,Vostrikova, O. S.,et al.
p. 242 - 244
(2007/10/02)

Dimethylboron Bromide and Diphenylboron Bromide: Cleavage of Acetals and Ketals
The cleavage of various acetal and ketal derivatives by the use of dialkyl- and diarylboron halides is described.Acetals and ketals readily react with dimethylboron bromide or diphenylboron bromide at -78 deg C to give the corresponding carbonyl compounds in excellent yield.Under similar reaction conditions MEM, MOM, and MTM ethers are smoothly converted to alcohols.Acetonides are also cleaved with dimethylboron bromide while THP and THF ethers and methyl glycosides react at room temperature.Mechanistic considerations of the cleavage reactions are presented.The chemoselective virtues of dimethylboron bromide are summarized.
Guindon, Yvan,Yoakim, Christiane,Morton, Howard E.
p. 3912 - 3920
(2007/10/02)

Hydroboration. 67. Cyclic Hydroboration of Acyclic α,ω-Dienes with 9-Borabicyclononane/Borane-Dimethyl Sulfide
Hydroboration of acyclic α,ω-dienes, 1,3-butadiene, 1,4-pentadiene, 1,5-hexadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,11-dodecadiene, and 1,13-tetradecadiene, with 2 molar equiv of 9-borabicyclononane (9-BBN), followed by redistribution of the resulting dumbbell-shaped trialkylboranes with 1 molar equiv of borane-methyl Sulfide complex (BMS), has been investigated.With 1,3-butadiene, the initial redistribution product, the five-membered boracyclane, borolane, underwent a rapid ring-opening reaction to give the known 1,6-diboracyclodecane. 1,4-Pentadiene and 1,5-hexadiene afforded the corresponding boracyclanes, borinane and borepane, in quantitative yields.With all other dienes, the initial redistribution products were polymeric.They were converted to the methyl esters by treatment with methanol, and these products were depolymerized into cyclic derivatives in 88-98percent yield by vacuum distillation at 175-200 deg C.In every case the cyclization was accompanied by varying amounts of isomerization so that the major products were both the parent B-methoxyboracyclane and the corresponding B-methoxy-2-n-alkylborinane.Thus, 1,6-heptadiene afforded B-methoxyborocane and B-methoxy-2-ethylborinane in 3:1 ratio and a total yield of 95percent.With 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene and 1,11-dodecadiene, the isomerized product constituted the major constituent of the distillate. 1,13-Tetradecadiene afforded the parent boracyclane and the isomer in a 47:53 ratio and a combined yield of 82percent.The B-methoxyboracyclanes were converted to the corresponding cyclic ketones by the DCME reaction in 55-65percent yield.
Brown, Herbert C.,Pai, Ganesh G.,Naik, Ramachandra G.
p. 1072 - 1078
(2007/10/02)