18829-55-5Relevant articles and documents
Reactivity of 3-Nitro-5,6-Dihydro-4H-Pyran with Organoalanes: Preparation of (E)-α, β-Ethylenic Aldehydes
Menicagli, Rita,Guagnano, Vito,Malanga, Corrado
, p. 1871 - 1876 (1994)
3-Nitro-5,6-dihydro-4H-pyran reacts with organoalanes and gives 1,4 addition products.In suitable hydrolysis conditions, the reaction results in the formation of aldehydes that are C1-homologues of the chain transferred by the alane.
A new stereoselective synthesis of trans-α, β- unsaturated carbonyl compounds.
Clinet, Jean-Claude,Linstrumelle, Gerard
, p. 3987 - 3990 (1980)
Allenic silylated ethers are efficient precursors to unsaturated carbonyl compounds.
Alkene-Zipper Catalyzed Selective and Remote Retro-ene Reaction of Alkenyl Cyclopropylcarbinol
Bruffaerts, Jeffrey,Vasseur, Alexandre,Marek, Ilan
, p. 1389 - 1396 (2018)
Reminiscent of biological systems, the increasingly popular concept of remote activation allows a greater strategic synthetic flexibility for the development of novel synthetic organic methodologies. In this Communication, we report that commercially available ruthenium (II)-based “alkene zipper catalyst” enables the selective transformation of a large variety of ω-alkenyl cyclopropylcarbinols into stereodefined unconjugated (E)-acyclic aldehydes bearing a quaternary stereocenter through an isomerization followed by a retro-ene reaction. To unravel this peculiar catalytic property of the “alkene zipper” and shed some light on the mechanism, a series of control experiments were performed. (Figure presented.).
An efficient Pd@Pro-GO heterogeneous catalyst for the α, β-dehydrogenation of saturated aldehyde and ketones
Pan, Gao-Fei,Wang, Zhe,Chang, Yi-Yuan,Hao, Yue,Wang, Yi-Chen,Xing, Rui-Guang
supporting information, (2021/12/30)
An Efficient Pd@Pro-GO heterogeneous catalyst was developed that can promote the α, β-dehydrogenation of saturated aldehyde and ketones in the yield of 73% ? 92% at mild conditions without extra oxidants and additives. Pd@Pro-GO heterogeneous catalyst was synthesized via two steps: firstly, the Pro-GO was obtained by the esterification reaction between graphene oxide (GO) and N-(tert-Butoxycarbonyl)-L-proline (Boc-Pro-OH), followed by removing the protection group tert-Butoxycarbonyl (Boc), which endowed the proline-functionalized GO with both the lewis acid site (COOH) and the bronsted base site (NH), besides, the pyrrolidine of proline also can form imine with aldehydes to activate these substrates; Second, palladium was dispersed on the proline-functionalized GO (Pro-GO) to obtained heterogeneous catalyst Pd@Pro-GO. Mechanistic studies have shown that the Pd@Pro-GO-catalyzed α,β-dehydrogenation of saturated aldehyde and ketones was realized by an improved heterogeneously catalyzed Saegusa oxidation reaction. Based on the obove characteristics, the Pd@Pro-GO will be widely used in the transition metal catalytic field.
Synthesis of (5Z,7E)-dodecane-5,7-diene-1-alcohol as well as acetate and propionate thereof
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Paragraph 0032-0034, (2019/03/28)
The invention belongs to the technical field of insect pheromone synthesis, and discloses a new method for synthesizing (5Z,7E)-dodecane-5,7-diene-1-alcohol as well as acetate and propionate thereof.The method takes propynol as an initial raw material to be subjected to coupling with 1-bromobutane to generate 2-heptyne-1-alcohol, triple bond is reduced to be E-type double bond through LiAlH4, 2-heptyne-1-alcohol is oxidized to be olefine aldehyde through PDC, olefine aldehyde reacts with a Wittig reagent (5-ethyoxyl-5-oxopentyl)triphenyl phosphonium bromide to produce (5Z,7E)-dodecane-5,7-dienoic acid ethyl ester which is reduced by LiAlH4 to obtain (5Z,7E)-dodecane-5,7-diene-1-alcohol, (5Z,7E)-dodecane-5,7-diene-1-alcohol reacts with acetyl chloride and propionyl chloride finally to obtain (5Z,7E)-dodecane-5,7-diene-1-alcohol acetate and (5Z,7E)-dodecane-5,7-diene-1-alcohol propionate. The method utilizes LiAlH4 to reduce the triple bond to be the E-type double bond, and utilizes theWittig reaction of the Wittig reagent with the tail end provided with ester group and aldehyde to directly build the Z-type double bond, the synthesis route is simple, convenient and efficient, and the reaction condition is moderate and environmentally friendly.
Fe3O4 Nanoparticles Anchored on Carbon Serve the Dual Role of Catalyst and Magnetically Recoverable Entity in the Aerobic Oxidation of Alcohols
Geng, Longlong,Zheng, Bin,Wang, Xiang,Zhang, Wenxiang,Wu, Shujie,Jia, Mingjun,Yan, Wenfu,Liu, Gang
, p. 805 - 811 (2016/03/05)
A composite of Fe3O4 nanoparticles anchored on a carbon support (Fe3O4/C), possessing both superparamagnetism and molecular oxygen activating properties, was prepared by an ammonia-assisted precipitation method. Fe3O4/C could catalyze the selective oxidation of various benzyl alcohols with air as the oxidant source, and could be easily separated and recycled with an external magnet. The small particle size and the interaction between the Fe3O4 nanoparticles and carbon support endow the Fe3O4/C catalyst with relatively high reducibility. Its oxidation state is easy to change. This intrinsic property of the Fe3O4 nanoparticles could be responsible for the high activity of Fe3O4/C in the aerobic oxidation of alcohols.
Highly enantioselective copper(i)-catalyzed conjugate addition of 1,3-diynes to α,β-unsaturated trifluoromethyl ketones
Sanz-Marco, Amparo,Blay, Gonzalo,Mu?oz, M. Carmen,Pedro, José R.
supporting information, p. 8958 - 8961 (2015/05/27)
The conjugate diynylation of α,β-unsaturated trifluoromethyl ketones is carried out in the presence of a low catalytic load (2.5 mol%) of a copper(i)-MeOBIPHEP complex, triethylamine and a terminal 1,3-diyne. Pre-metalation of the terminal 1,3-diyne with stoichiometric or higher amounts of dialkylzinc reagent is not required. The corresponding internal diynes bearing a propargylic stereogenic center are obtained with good yields and excellent enantioselectivities. This journal is
Synthesis of α,β-unsaturated aldehydes and nitriles via cross-metathesis reactions using Grubbs' catalysts
Rountree, Sandra M.,Taylor, Sarah F.R.,Hardacre, Christopher,Lagunas, M. Cristina,Davey, Paul N.
, p. 94 - 104 (2015/09/28)
A series of α,β-unsaturated aldehydes and nitriles of significant interest in the fragrance industry have been prepared using Grubbs' catalysts in cross-metathesis reactions of electron-deficient olefins (i.e., acrolein, crotonaldehyde, methacrolein, and acrylonitrile) with various 1-alkenes, including 1-decene, 1-octene, 1-hexene and 2-allyloxy-6-methylheptane. The latter is of particular interest, as it has not previously being used as a substrate in cross-metathesis reactions and allows access to valuable intermediates for the synthesis of new fragrances. Most reactions gave good selectivity of the desired CM product (≥90%). Detailed optimisation and mechanistic studies have been performed on the cross-metathesis of acrolein with 1-decene. Recycling of the catalyst has been attempted using ionic liquids.
Iron-catalyzed aerobic oxidation of allylic alcohols: The issue of C=C bond isomerization
Liu, Jinxian,Ma, Shengming
supporting information, p. 5150 - 5153 (2013/11/06)
An aerobic oxidation of allylic alcohols using Fe(NO3) 3·9H2O/TEMPO/NaCl as catalysts under atmospheric pressure of oxygen at room temperature was developed. This eco-friendly and mild protocol provides a convenient pathway to the synthesis of stereodefined α,β-unsaturated enals or enones with the retention of the C-C double-bond configuration.
Evaluation of the formation and stability of hydroxyalkylsulfonic acids in wines
De Azevedo, Luciana C.,Reis, Marina M.,Motta, Luiz F.,Da Rocha, Gisele O.,Silva, Luciana A.,De Andrade, Jailson B.
scheme or table, p. 8670 - 8680 (2009/09/28)
The presence of carbonyl compounds (CCs) in wines has sparked the interest of researchers in several countries. The quantification of some of these compounds has been used as a parameter of quality for many fermented beverages. Although present in minute quantities (except for acetaldehyde), they have a strong olfactory impact. In addition, the CCs found in wines have a strong affinity for bisulfite and can form stable adducts, which will also interfere in the characteristics of aroma. The greatest challenge, however, is to predict which CCs have the strongest affinity for S(IV) and what conditions favor this interaction. To better understand the reaction of CC-bisulfite adduct formation (HASA), this study has evaluated the profile of 22 CCs in a "synthetic wine" containing bisulfite and in 10 real samples of different wines from the Sao Francisco Valley, northeastern Brazil. On the basis of principal component analysis (PCA) and dissociation constants, the results revealed that aliphatic aldehydes form adducts with S(IV), whereas ketones, cyclic aldehydes, and trans-alkenes interact weakly and are found predominantly in their free form. These results revealed also that pH 10 and 11 were defined as the most appropriate for CC-SO2 adduct dissociation, and the total CCs were quantified reliably.
