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Chlorodiphenylphosphine, imidazole, and molecular iodine in refluxing dichloromethane are used for the efficient preparation of amides under mild reaction conditions. This reagent system also shows excellent selectivity for mono-Nalkylation of amines with alcohols. In this system, the resulting phosphorus byproduct (diphenylphosphinic acid) is easily removed by extraction using an aqueous basic solution in the workup processes, which avoids the tedious and time-consuming chromatographic methods. Key words: benzylation, amidation, imidazole, amine, alcohol, carboxylic acid, chlorodiphenylphosphine, iodine. On a utilise un melange de chlorodiphenylphosphine, d'imidazole et d'iode moleculaire dans le dichloromethane au reflux pour preparer des amides d'une facon efficace, dans des conditions douces. Ce systeme de reactifs presente aussi une bonne selectivite pour la mono-N-alkylation d'amines avec des alcools. Dans ce systeme, il est facile d'eliminer le sous-produit phosphore, l'acide diphenylphosphinique, par extraction du melange reactionnel a l'aide d'une solution basique aqueuse qui evite les methodes chromatographiques lentes et ennuyeuses. Mots-cles : benzylation, amidation, imidazole, amine, alcool, acide carboxylique, chlorodiphenylphosphine, iode., Introduction For many years, phosphines as reagents or catalysts have been employed for various organic transformations. Among these, soluble triphenylphosphine (TPP) has found significant attention, and several applications of this [...]

A new synthetic method is developed for preparing propargylic alcohols from epoxides and terminal alkynes through 1,2-shifts. The synthetic method is useful for both electron-rich and electron-deficient alkynes with other acid and base-sensitive functional groups because of the mild conditions to pre-activate alkynes with silver nitrate.

The studies about the hydrodynamic behavior of high molar mass polyglycidol in water and dilute aqueous solution and its scaling exponents are reported. The scaling exponent is found to increase with increasing molar mass which confirm the elongated coil-formation in the high molar mass region.

Indium promoted coupling of propargyl aldehydes with allyl halides has resulted in the synthesis of propargyl alcohols under aqueous and organic conditions. Oxy-Cope rearrangement of 4-hydroxy-1-ene-5-ynes followed by a secondary addition step under highly basic conditions has led to the formation of lactol.

Acetaldehyde is the first active breakdown product (i.e., metabolite) generated during alcohol metabolism. It has toxic properties but also exerts other actions on the body (i.e., has pharmacological properties). Recent [...]

Cigarette and alcohol use often develop concurrently, and smoking is especially common among youth treated for alcohol and other drug (AOD) use disorders. Special considerations for adolescent smoking cessation treatment [...]

A series of chiral vanadyl carboxylates derived from N-salicylidene-L-[alpha]-amino acids and vanadyl sulfate has been developed. These configurationally well defined complexes were examined for the kinetic resolution of double- and mono-activated 2[degrees] alcohols. The best chiral templates involve the combination of L-tert-leucine and 3,5-di-t-butyl-, 3,5-diphenyl-, or 3,4-dibromo-salicylaldehyde. The resulting vanadyl(V)-methoxide complexes after recrystallization from air-saturated methanol serve as highly enantioselective catalysts for asymmetric aerobic oxidation of s-hydroxyl-esters and amides with a diverse array of [alpha]-, O-, and N-substituents at ambient temperature in toluene, The asymmetric inductions of the oxidation process are in the range of 10 to >100 in terms of selectivity factors ([k.sub.rel]) in most instances. The previously undescribed aerobic oxidation protocol is also applicable to the kinetic resolution of C-13 taxol side chain with high selectivity factor ([k.sub.rel] = 35). X-ray crystallographic analysis of an adduct between a given vanadyl complex and N-benzyl-mandelamide allows for probing the stereochemical origin of the nearly exclusive asymmetric control in the oxidation process. alcohol oxidation | [alpha]-hydroxy acids | asymmetric catalysis | vanadyl(V) methoxides

Even though there is a large body of information concerning the harmful effects of alcohol on different organisms, the mechanism(s) that affects developmental programs, at a single-cell level, has not been clearly identified. In this respect, the spore-forming bacterium Bacillus subtilis constitutes an excellent model to study universal questions of cell fate, cell differentiation, and morphogenesis. Here, we demonstrate that treatment with subinhibitory concentrations of alcohol that did not affect vegetative growth inhibited the initiation of spore development through a selective blockage of key developmental genes under the control of the master transcription factor Spo0A~P. Isopropyl-[beta]-o-thiogalactopyranoside-directed expression of a phosphorylation-independent form of Spo0A (Sad67) and the use of an in vivo mini-Tn10 insertional library permitted the identification of the developmental SinR repressor and RapA phosphatase as the effectors that mediated the inhibitory effect of alcohol on spore morphogenesis. A double rapA sinR mutant strain was completely resistant to the inhibitory effects of different-C-length alcohols on sporulation, indicating that the two cell fate determinants were the main or unique regulators responsible for the spo0 phenotype of wild-type cells in the presence of alcohol. Furthermore, treatment with alcohol produced a significant induction of rapA and sinR, while the stationary-phase induction of sinI, which codes for a SinR inhibitor, was completely turned off by alcohol. As a result, a dramatic repression of spo0A and the genes under its control occurred soon after alcohol addition, inhibiting the onset of sporulation and permitting the evaluation of alternative pathways required for cellular survival.

The synthesis of different stereospecifically deuterium-labeled and isotopically tagged palmitic acid probes needed to decipher the stereospecifically course of the T. pityocampa delta(super 11) desaturase is described. The synthesis of probes is carried out by a chemoenzymatic route, in which the key step is the kinetic lipase-catalyzed resolution of racemic mixtures of secondary propargyl alcohols.

A simple and efficient protocol, which is inexpensive, convenient, clean, and facile, for oxidation of alcohols to carbonyl compounds has been developed using sodium hypochlorite in the presence of [beta]-cyclodextrin with water as solvent. A series of alcohols were oxidized at room temperature in excellent yields. Key words: oxidation, alcohols, sodium hypochlorite, KBr, [beta]-cyclodextrin, biomimetic, water. On a mis au point un protocole simple et efficace d'oxydation des alcools en composes carbonyles qui est peu couteux, pratique, propre, et facile et qui fait appel a l'utilisation d'hypochlorite de sodium en presence de [beta]-cyclodextrine dans l'eau comme solvant. On a oxyde une serie d'alcools, a la temperature ambiante, avec d'excellents rendements. Mots cles: oxydation, alcools, hypochlorite de sodium, KBr, [beta]-cyclodextrine, biomimetique, eau. [Traduit par la Redaction]

An investigation on the state-to-state of vibrational energy relaxation of the OH-stretch fundamental is presented. The time-dependent Schrodinger equation (TD) results are compared to the Landau-Teller theory (LT) results and the key differences are highlighted.

Studies done on liquid-liquid phase splitting in ternary mixtures that contain a room-temperature ionic liquid and an alcohol aqueous solution -namely, [bmim][PF6] + ethanol + water and [bmim] [NTf2] + 2-methypropanol + water using a He-Ne laser light-scattering method is reported. It was found that both ternary mixtures exhibit a very pronounced water-alcohol co-solvent effect.

The rate at which single-bubble sonoluminescence is quenched in the presence of alcohol is examined, and single-bubble sonoluminescence bubbles are generated in a partially degassed-argon-water/alcohol mixture. Quenching requires the repetitive injection of alcohol molecules, which leads to the accumulation of gaseous products within the bubbles.

Nanosecond laser flash photolysis of coniferyl alcohol and isoeugenol in acetonitrile leads to the formation of transient species that are identified as the corresponding radical cations. These radical cations decay with rate constants of ca. 1 x [10.sup.6] [s.sup.-l] in dry acetonitrile. Both radical cations react rapidly with hydroxylic solvents like water and alcohols to give 4-vinylphenoxyl radicals, indicating that these reagents behave as bases rather than nucleophiles. In addition, anionic reagents (acetate, cyanide, and chloride) react rapidly with the radical cations with second-order rate constants that are close to diffusion controlled. The main products generated in the presence of the anionic reagents are again the 4-vinylphenoxyl radicals, suggesting that these reagents also behave as bases. The lifetime of the radical cations in acidic acetonitrile was found to increase dramatically due to a shift in the radical cation--vinyl phenoxyl radical acid-base equilibrium to the side of the radical cation. An estimate of the p[Kapp].sub.a] of the radical cation in acetonitrile of 4.0 was obtained from the data. Key words: radical cations, laser flash photolysis, lignan, vinylphenols.

1,1,1-trifluoropropan-2-ol (TFIP) alcohol is used to study the influence of trifluoromethyl groups (CF3) on the physicochemical properties of fluorinated organic molecules. The difference in organization of hydration shell around the CF3 and CH3 groups helped in determining the trifluoromethanol and 1,1,1,3,3,3-hexafluropropano-2-ol.

The 1:1 electron donor-acceptor complexes of CO2 formed with alcohols, methanol and ethanol, and with acetone in context of ab initio calculations are examined. The division of the v(sub 2) bending mode of CO2 and v(sub s)(OH) stretching mode of alcohols or the anti symmetric v(sub a)(CCC) and symmetric v(sub s)(CO) stretching modes of acetone are highlighted.

ArF laser photodissociation dynamics of 1,4-pentadien-3-ol is presented. While the lazer-induced fluorescence indicate that only 1.1 percent of the nascent OH are produced in the vibratonally excited state with v = 1, there is no OH produced with v = 2.

Derivatives of 1-phenoxy-2-alkanols were kinetically resolved by esterification with irreversible and reversible acyl donors using lipase B from Candida antarctica (Novozyme 435) as a catalyst. To optimize the relative rate of reaction (the E-value), esterifications in eight different solvents with different water activities were performed. For 3-bromo-1-phenoxy-2-propanol (1), the E-values in all the solvents were higher when the water activity was increased, while the E-values for 1-phenoxy-2-pentanol (2) and 3-chloro-1-phenoxy-2-propanol (3) decreased by increasing water activity. The water content of the various reaction media with the same water activity was determined. Solvents such as 1,4-dioxane, acetonitrile, and tetrahydrofuran contained much more water than hexane, carbon tetrachloride, cyclohexane, toluene, and benzene. At high-water activity, the high-water content of the former group of solvents resulted in termination of the reaction at low conversion. The reason seemed to be that the acyl donor and possibly also the produced esters were hydrolyzed. This was not the case when the esterification was performed in water-immiscible solvents with the same water activity. Key words: kinetic resolution, E-value, solvents, water activity, water content.

Epoxy tert-alcohols have been prepared from (E)-enones in a two-step approach consisting of Julia--Colonna asymmetric epoxidation followed by Grignard alkylation of the epoxyketone. On treatment with sub-stoichiometric amounts of Yb[(OTf).sub.3] these trans-epoxyalcohols underwent efficient stereoselective semi-pinacol rearrangement to afford anti-[alpha]-phenyl-[beta]-hydroxy-ketones (aldols). Under the same conditions, spirocyclic epoxyalcohols derived from 1-tetralone and 1-benzosuberone undergo either ring contraction (via semi-pinacol rearrangement) or fragmentation. A mechanistic rationale is presented to explain the formation of the various products. Key words: Julia-Colonna reaction, asymmetric epoxidation, epoxy tert-alcohols, semi-pinacol rearrangement.

Research has been conducted on the omega-alkynals that yield macrocyclic (S)-allylic alcohols. The ligand type, reproducibility and the size and nature of the macrocycle have been investigated to study the macrocyclization methodology.

Research has been conducted on beta-azido alcohols. Enzymatic resolution of these alcohols in combination with ruthenium-catalyzed alcohol isomerization has been investigated.

Research has been conducted on the methyl group deprotonation on silicon group. The methodology for this deprotonation based on the intramolecular pyridyl group coordination is discussed.

Research has been conducted on the silylketene dithiocetal reaction with aldehydes. The reaction resulting in deoxygenation divinylation products in the presence of Lewis acid is described.

The polymer-supported proline-based diamine catalyst efficiently resolves the racemic mixtures of secondary alcohols with products separated chromatographically. The reactions are fully automatable without an aqueous workup and the catalyst can be recovered and reused.

Results show that molecular oxygen oxidizes primary and secondary alcohols at ambient temperature using N-hydroxyphthalimide and cobalt(II) ion as the catalyst. Data indicate that this reaction is economical and environmentally sound for the conversion of alcoholic functions to carbonyl groups.

Research describes a method for reduction of primary alcohols and ethers with hydrosilane aided deprotection of aryl alkyl ethers in the presence of B(C(sub)6F(sub)5)(sub)3. The mechanistic aspects of the reaction are presented.

The pressure dependence of interfacial tension at various compositions was measured and the experimental results were analyzed thermodynamically through the study of the miscibility of 1-icosanol (C20OH) and 1,1,2,2-tetrahydroheptadecafluorodecanol (FC10OH) in the adsorbed film at the hexane/water interface. It was found that the alcohol molecules become less miscible and therefore the activity coefficients of alcohols become larger in the expanded state with increasing pressure.

Research into the reactions of alcohols and alkenes with hydrogen-terminated silicon surfaces is presented. It is possible to use molecular hydrosilanes containing Si-H2, Si-H and Si-HD as models for some properties of hydrogen-terminated and deuterated porous silicon and abraded silicon surfaces.

Research points out that simple amino acids can be used as ligands in the ruthenium(II)-catalyzed transfer hydrogenation of aryl alkyl ketones. The bicyclic beta-amino alcohols are obtained by simple aza-Diels-Alder adduct formation between cyclopentadiene and iminium ion and adduct's subsequent reduction.

Research describes the synthesis of N,S-chelates that function as ligands for the iridium-(I)-catalyzed transfer hydrogenation of prochiral ketones. Data indicate that the aminosulfide is the best ligand for controlling asymmetric iridium-catalyzed transfer hydrogenation of prochiral ketones.

Research discusses the stereoselectivity of the Pummerer reaction and its application for the synthesis of densely functionalized L-alpha-trifluoromethyl (Tfm)-threoninate and D-alpha-Tfm-allo-threoninate in one-pot protocol involving treatment of the diasteromeric sulfenamides with sodium borohydride.

The synthetic route for preparing enantiomerically pure beta-amino alcohols involves asymmetric addition of enaniopure alkyl p-tolyl sulfoxide anions to (S)-N-benzylidene-p-tolyenesulfinamide followed by a stereospecific non-oxidative Pummerer reaction yielding beta-amino sulfoxide. The procedure is adoptable to large-scale processes.

Research presents a methodology for one-pot conversion of a hydroxy group into an iodo group using cerium(III)chloride Lewis acid. Data indicate that iodides can be prepared from alcohols using cerium(III)chloride/sodium iodide system in acetonitrile.

Results show that the carboxymethylation of a homoallylic alcohol occurs via iodolactonization mediated by iodonium dicollidine hexafluorophosphate. The substitution of the iodide with silver trifluoroacetate instead of chloroacetic acid results in the diastereoselective syn-syn dihydroxylation of the double bond in cyclic alkene and possibly with the cyclic allylic alcohols as well.

Research describes the synthesis of multigram quantities of the primary alcohols, in good yields, following a diazo-insertion strategy, which facilitates a convergent synthesis of the title compound. Data indicate that the acyloxazolidinone moiety serves as a surrogate for the primary alcohol.

Two step synthesis of functionalized and sterically hindered CF(sub)3-substituted alkenes from trifluoroacetic esters is described. The synthetic strategy leads to geometriclly pure gamma-CF(sub)3, gamma-alkyl allylic alcohols, which rearrange and form a CF(sub)3-substtituted quaternary carbon upon ortho ester or amide acetal treatment.

The mechanism of acyclic allylic alcohols epoxidation, how the spiro/planar geometry influences it, and the relative stability of transition structure are discussed. Data indicate that anti transition structures do not contribute much to the stereochemical outcomes. Results are interpreted using density functional calculations.

The hydroperoxide rearrangement leads to the formation of alpha-phenoxyhydroperoxide, geminal dihydroperoxide, and bis(hydroperoxy)-dialkyl-peroxide moieties, suggesting tertiary alcohol transforms into hydroperoxide during this rearrangement chemistry.

Research has been conducted on the alcohol containing HCl. Transformation of hydroquinone reduction-products of helicenebisquinones into p-alkoxyphenols is described.

Research has been conducted on the benzyl alcohol potential energy surface. The exploration of this energy surface at the RHF/6-31G and MP2-(full)/6-31G level of ab initio theory is described.

Research has been conducted on the isomeric purification of 3-bromopropenols. The range of Wittig reagents exploration and application of the methodology in natural product synthesis are discussed.

Research has been conducted on the asymmetric synthesis of (+)-dihydrokawain-5-ol. Experiments with furan ring degradation in the furyl alcohol are discussed.

Research has been conducted on the aryl alcohols absolute configuration. The results of the CD exciton chirality method are presented.