79-91-4Relevant academic research and scientific papers
Sunlight-induced C–C bond formation reaction: Radical addition of alcohols/ethers/acetals to olefins
Hayakawa, Mamiko,Shirota, Hisashi,Hirayama, Souta,Yamada, Ryuusei,Aoyama, Tadashi,Ouchi, Akihiko
, (2021/04/09)
A sunlight-induced C–C bond formation reactions upon the addition of alcohols/ethers/acetals to olefins proceeded efficiently using di-tert-butyl peroxide (DTBP). The reactions proceeded faster than many of the previously reported sunlight and many conventional lamp photolyses, typically in 3–4 h under irradiation with sunlight, in excellent yield using olefins bearing two electron withdrawing groups (EWGs) (product yield > 95 %) and in good to fair yield with olefins bearing one EWG. The yields observed for some products were ～20 % higher than those obtained using a conventional Xe lamp as the light source, which was confirmed to be due to a light intensity effect. Gram-scale experiments showed similar yields to those observed in their corresponding small-scale experiments.
Site-selectivity in TBADT-photocatalyzed C(sp3)H functionalization of saturated alcohols and alkanes
Fukuyama, Takahide,Yamada, Keiichi,Nishikawa, Tomohiro,Ravelli, Davide,Fagnoni, Maurizio,Ryu, Illhyong
supporting information, p. 207 - 209 (2018/02/07)
Site-selectivity in C(sp3)H functionalization of aliphatic alcohols and alkanes was studied using the decatungstate anion as a photocatalyst. In the case of aliphatic alcohols, CH bond a to the hydroxy group was preferentially functionalized. The a-site-selectivity is rationalized by polar effects imparted by the hydroxy group in the SH2 transition states. In contrast, CH functionalization of alkanes was largely affected by steric effects.
Continuous-Flow Preparation of γ-Butyrolactone Scaffolds from Renewable Fumaric and Itaconic Acids under Photosensitized Conditions
Gérardy, Romaric,Winter, Marc,Horn, Clemens R.,Vizza, Alessandra,Van Hecke, Kristof,Monbaliu, Jean-Christophe M.
supporting information, p. 2012 - 2017 (2017/12/26)
The method and results described herein concern the photosensitized addition of various alcohols to renewable platform fumaric and itaconic acids under scalable continuous-flow conditions in glass micro- and mesofluidic reactors. Alcohols were used both as reagents and as solvents, thus contributing to a reduced environmental footprint. Process parameters such as the temperature, light intensity, and the nature as well as amount of the photosensitizer were assessed under microfluidic conditions and, next, transposed to a lab-scale mesofluidic reactor connected with an in-line NMR spectrometer for real-time reaction monitoring. Substituted γ-butyrolactones, including spiro derivatives with unique structural features, were obtained with quantitative conversion of the starting materials and in 47-76% isolated yields. The model photoaddition of isopropanol to fumaric acid was next successfully transposed in a pilot-scale continuous-flow photoreactor to further demonstrate scalability.
Photochemical C-C bond formation between alcohols and olefins by an environmentally benign radical reaction
Ouchi, Akihiko,Liu, Chuanxiang,Kaneda, Masayuki,Hyugano, Takeshi
supporting information, p. 3807 - 3816 (2013/07/25)
A radical C-C bond formation between olefins and alcohols proceeded efficiently by simple light irradiation at room temperature. The reaction proceeded in the presence of commercially available tBuOOtBu without using the harmful elements and/or compounds that have an unpleasant smell that are often used in conventional radical reactions. In addition, the reaction did not require photosensitizers or photocatalysts, which eliminated the time-consuming separation of sensitizers after the reaction, or the synthesis of photocatalysts as reported in previous procedures. A radical C-C bond formation between olefins and alcohols proceeded efficiently by simple light irradiation at room temperature without using the harmful elements often used in conventional radical reactions. Copyright
Microflow photochemistry - A reactor comparison study using the photochemical synthesis of terebic acid as a model reaction
Aida, Shin,Terao, Kimitada,Nishiyama, Yasuhiro,Kakiuchi, Kiyomi,Oelgem?ller, Michael
, p. 5578 - 5581 (2012/11/13)
The continuous-microflow photochemical synthesis of terebic acid from maleic acid was investigated in two different microreactor set-ups. The results were subsequently compared to analogue experiments in a conventional chamber reactor. Based on conversion rates, reactor design and energy efficiency calculations, the simple microcapillary reactor showed the best overall performance.
COSMETIC OR DERMATOLOGICAL COMPOSITION COMPRISING A POLYMER BEARING JUNCTION GROUPS, AND COSMETIC TREATMENT PROCESS
-
, (2010/10/03)
The present patent application relates to a cosmetic or dermatological composition comprising, in a cosmetically or dermatologically acceptable medium, a polymer comprising: (a) a polymer backbone that may be obtained by reaction: of a polyol comprising 3 to 6 hydroxyl groups;of a monocarboxylic acid containing 6 to 32 carbon atoms;of a polycarboxylic acid comprising at least two carboxylic groups COOH, and/or of a cyclic anhydride such as a polycarboxylic acid and/or of a lactone comprising at least one carboxylic group COOH; and(b) at least one junction group linked to the said polymer backbone and capable of establishing H bonds with one or more partner junction groups, each pairing of a junction group involving at least three H (hydrogen) bonds. The patent application also concerns a cosmetic treatment process using the said composition.
Synthesis of γ-lactols, γ-lactones and 1,4-monoprotected succinaldehydes under moderately concentrated sunlight
Dondi, Daniele,Protti, Stefano,Albini, Angelo,Carpio, Sonia Manas,Fagnoni, Maurizio
experimental part, p. 1653 - 1659 (2010/05/19)
The usefulness of solar light for carrying out photocatalytic reactions involving the formation of a carbon-carbon bond has been explored. Thus, some radical alkylations of α,β-unsaturated acids or aldehydes have been carried out in a mixed aqueous solution. Under these conditions, alkyl radicals are generated from i-PrOH and 1,3-dioxolane by photocatalyzed hydrogen abstraction. A water soluble photocatalyst (disodium benzophenondisulfonate, BPSS) was used, which greatly simplifies work up. With reasonably efficient radical traps (e.g. maleic acid), the syntheses could be carried out up to completion on a 10 gram scale within 10-15 hours exposure to sunlight in a solar concentrator (SOLFIN apparatus) in November in Almeria (Spain). The alkylation of some α,β-unsaturated aldehydes have been likewise performed under the same conditions. The Royal Society of Chemistry 2009.
Chemistry at Rigid Surfaces, 6. - Photochemically Induced Reactions with Surface-bound Sensitizers
Horner, Leopold,Klaus, Joachim
, p. 792 - 810 (2007/10/02)
AerosilR reacts with 3-triethoxysilylpropylamine to give Aminoaerosil (1) which can be converted into aerosils 2a - f by means of sensitizers containing carboxyl groups.The density of the functional groups on the surface which was determined by several methods clearly effects the reaction.On irradiation in 2-propanol, acetone was produced as well as the surface-bound pinacol, e. g. 4, which could be reoxidized by lead tetraacetate to give 2b.Hydrodimerization on the surface of 2b proceeds three times more slowly than with the homogeneous analogues.The photoreduction of 2b with a minor surface density, gave - in addition to 4 - the carbinol 8 and the mixed pinacol 9. - The aerosil with surface-bound p-acetylbenzoic acid (modified aerosil 2b) is investigated in comparison to the homogeneous system: experiments were made in (S)-p-menth-3-yl lactate and (R,S)-p-menth-3-yl-lactate.In both cases the surface-bound pinacol 4 was formed, and in the latter case a decrease in the optical activity of the lactate was observed. - With surface-bound sensitizers the following photochemically induced reactions were studied: a) the photosensitized addition of 2-propanol to maleic acid and diethyl maleate to give terebinic acid (12a) or its methyl ester, respectively; b) the sensitized cis/trans isomerization of maleic acid or diethyl fumarate; c) the sensitized cis/trans isomerization of 1,2-diphenylcyclopropane; d) the sensitized autoxidation of 2,5-dimethylfuran. - All four reactions, although slower, yield the same products as in the analogous homogeneous system.In reaction b), c), and d) the efficiency factor WF (ratio of reaction rates in homo- and heterogeneous system) and the reutilization factor SF (ratio of co nversions after a given time in the first and second experiment) was determined for the heterogeneous sensitizer.
