62660-02-0Relevant academic research and scientific papers
Preparation of Highly Reactive Metal Powders. A New Procedure for the Preparation of Highly Reactive Zinc and Magnesium Metal Powders
Rieke, Reuben D.,Li, Percy Tzu-Jung,Burns, Timothy P.,Uhm, Sung T.
, p. 4323 - 4324 (1981)
Highly reactive zinc and magnesium metal powders can be prepared by the lithium reduction of the corresponding metal salt with a catalytic amount of naphthalene as an electron carrier.Applications to the Reformatsky reaction, the Grignard reaction, and cyclopropanation (with dibromomethane) are described.
Access to β-Hydroxyl Esters via Copper-Catalyzed Reformatsky Reaction of Ketones and Aldehydes
Ouyang, Lu,Liao, Jian Hua,Xia, Yan Ping,Luo, Ren Shi
supporting information, p. 1418 - 1422 (2020/10/02)
An efficient and simple Cu-catalyzed Reformatsky reaction of ketones and aldehydes has been accomplished with ethyl iodoacetate. Excellent yields of β-hydroxyl esters were achieved with a range of ketones and aldehydes, which varied from aromatic to aliphatic, unsaturated to saturated ketones and aldehydes. This practical and convenient transformation was conducted with inexpensive, readily available, and commercial starting materials under mild reaction conditions.
Synthesis method of beta-hydroxy ester compound
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Paragraph 0121-0127, (2020/07/12)
The invention belongs to the technical field of medicine and organic chemical synthesis, and discloses a synthesis method of a beta-hydroxy ester compound. An aldehyde compound and an iodo-acetate compound are used as raw materials; manganese powder is adopted as an accelerant, metal nickel salt is adopted as a catalyst and an organic solvent is adopted as a reaction medium, an organic protonic acid is added and stirred and reacted under inert gas protection, the reaction system is cooled to room temperature after the reaction is finished, vacuum distillation and concentration are performed toobtain a crude product, and column chromatography purification is performed to obtain the beta-hydroxy ester compound. The synthesis method is safe and simple to operate, raw materials are easy to obtain, the price is low, the reaction efficiency is high, and the yield can reach 90% or above and even reach 98%; the method is good in functional group adaptability, wide in substrate adaptability, environmentally friendly, beneficial to industrial production and wide in application in medicine and organic synthesis.
Iron(0)-Mediated Reformatsky Reaction for the Synthesis of β-Hydroxyl Carbonyl Compounds
Liu, Xuan-Yu,Li, Xiang-Rui,Zhang, Chen,Chu, Xue-Qiang,Rao, Weidong,Loh, Teck-Peng,Shen, Zhi-Liang
supporting information, p. 5873 - 5878 (2019/08/20)
An efficient, economical, and practical Reformatsky reaction of α-halo carbonyl compounds with aldehydes/ketones by using cheap and commercial iron(0) powder as reaction mediator is developed. The reactions proceeded effectively in the presence of a catalytic amount of iodine (20 mol %) to afford the synthetically useful β-hydroxyl carbonyl compounds in moderate to good yields.
A Ball-Milling-Enabled Reformatsky Reaction
Cao, Qun,Stark, Roderick T.,Fallis, Ian A.,Browne, Duncan L.
, p. 2554 - 2557 (2019/06/17)
An operationally simple one-jar one-step mechanochemical Reformatsky reaction using in situ generated organozinc intermediates under neat grinding conditions has been developed. Notable features of this reaction protocol are that it requires no solvent, no inert gases, and no pre-activation of the bulk zinc source. The developed process is demonstrated to have good substrate scope (39–82 % yield) and is effective irrespective of the initial morphology of the zinc source.
Bu 4 N + -Controlled Addition and Olefination with Ethyl 2-(Trimethylsilyl)acetate via Silicon Activation
Das, Manas,Manvar, Atul,Fox, Ian,Roberts, Dilwyn J.,O'Shea, Donal F.
supporting information, p. 2401 - 2406 (2017/09/30)
Catalytic Bu 4 NOAc as silicon activator of ethyl 2-(trimethylsilyl)acetate, in THF, was utilized for the synthesis of β-hydroxy esters, whereas employing catalytic Bu 4 NOTMS gave α,β-unsaturated esters. The established reaction conditions were applicable to a diverse range of aromatic, heteroaromatic, aliphatic aldehydes and ketones. Reactions were achieved at room temperature without taking any of the specialized precautions that are in place for other organometallics. A stepwise olefination pathway via silylated β-hydroxy esters with subsequent elimination to form the α,β-unsaturated ester has been demonstrated. The key to selective product formation lies in use of the weaker acetate activator which suppresses subsequent elimination whereas stronger TMSO - activator (and base) facilitates both addition and elimination steps. The use of tetrabutyl ammonium salts for both acetate and trimethylsilyloxide activators provide enhanced silicon activation when compared to their inorganic cation counterparts.
N-heterocyclic carbene mediated Reformatsky reaction of aldehydes with a-trimethylsilylcarbonyl compounds
Zou, Xiao-Lei,Du, Guang-Fen,Sun, Wan-Fu,He, Lin,Ma, Xiao-Wei,Gu, Cheng-Zhi,Dai, Bin
, p. 607 - 612 (2013/07/27)
N-Heterocyclic carbenes have been employed as highly efficient organocatalysts to mediate silyl-Reformatsky type reaction. In the presence of only 0.5 mol % nucleophilic carbene 1, various aldehydes coupled with α-trimethylsilylethylacetate very smoothly in DMF at room temperature to provide the corresponding β-hydroxyesters in moderate to high yields. α-Trimethylsilylketone and α-trimethylsilylamide can also undergo the addition reaction to give β-hydroxyketone and b-hydroxyamide in moderate yields.
P(i-PrNCH2CH2)3N: Efficient catalyst for synthesizing β-hydroxyesters and α,β-unsaturated esters using α-trimethylsilylethylacetate (TMSEA)
Wadhwa, Kuldeep,Verkade, John G.
supporting information; experimental part, p. 4368 - 4371 (2009/09/06)
(Chemical Equation Presented) We present an efficient synthesis of β-hydroxyesters and R,β-unsaturated esters via activation of the silicon-carbon bond of α-trimethylsilylethylacetate using catalytic amounts of the commercially available P(i-PrNCH2CH2) 3N 1a. Selectivity for either of these two products can be achieved simply by altering the catalyst loading and reaction temperature to afford addition or stereoselective condensation. This method is mild and tolerates a wide array of functional groups.
Temporary silicon connection strategies in intramolecular allylation of aldehydes with allylsilanes
Beignet, Julien,Jervis, Peter J.,Cox, Liam R.
, p. 5462 - 5475 (2008/12/21)
(Chemical Equation Presented) Three γ-(amino)silyl-substituted allylsilanes 14a-c have been prepared in three steps from the corresponding dialkyldichlorosilane. The aminosilyl group has been used to link this allylsilane nucleophile to a series of β-hydroxy aldehydes through a silyl ether temporary connection. The size of the alkyl substituents at the silyl ether tether governs the outcome of the reaction on exposure to acid. Thus, treatment of aldehyde (E)-9aa, which contains a dimethylsilyl ether connection between the aldehyde and allylsilane, with a range of Lewis and Bronsted acid activators provides an (E)-diene product. The mechanism of formation of this undesired product is discussed. Systems containing a sterically more bulky diethylsilyl ether connection react differently: thus in the presence of TMSOTf and a Bronsted acid scavenger, intramolecular allylation proceeds smoothly to provide two out of the possible four diastereoisomeric oxasilacycles, 23 (major) and 21 (minor). A diene product again accounts for the remaining mass balance in the reaction. This side product can be completely suppressed by using a sterically even more bulky diisopropylsilyl ether connection in the cyclization precursor, although this is now at the expense of a slight erosion in the 1,3-stereoinduction in the allylation products. The sense of 1,3-stereoinduction observed in these intramolecular allylations has been rationalized by using an electrostatic argument, which can also explain the stereochemical outcome of a number of related reactions. Levels of 1,4-stereoinduction in the intramolecular allylation are more modest but can be significantly improved in some cases by using a tethered (Z)-allylsilane in place of its (E)-stereoisomer. Oxidation of the major diastereoisomeric allylation product 23 under Tamao-Kumada conditions provides an entry into stereodefined 1,2-anti-2,4-syn triols 28.
Dimethylzinc-mediated, oxidatively promoted Reformatsky reaction of ethyl iodoacetate with aldehydes and ketones
Cozzi, Pier Giorgio,Mignogna, Alessandro,Vicennati, Paola
supporting information; experimental part, p. 975 - 978 (2009/05/27)
A practical and general Reformatsky reaction, promoted by oxidants and mediated by dimethylzinc, is described. The reaction is fast and runs at 0°C with aldehydes and ketones, under mild reaction conditions. Preliminary results obtained for the enantioselective version show that inexpensive chiral amino alcohols could be used in the challenging formation of enantioenriched quaternary stereogenic centers.
