1660-05-5Relevant academic research and scientific papers
Asymmetric tertiary alcohol and (meth) acrylic ester production method (by machine translation)
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, (2016/10/08)
The invention provides a method for easily preparing an asymmetric tertiary alcohol having a ring-shaped framework with a high yield even if a metallic compound with high toxicity is not used. In addition, the invention provides a method for obtaining a (methyl) acrylic ester which contains the tertiary alcohol having the ring-shaped framework with a high yield. The method for preparing the asymmetric tertiary alcohol at least contains a process (A) and a process (B). Process (A): adding liquid containing a specific organometallic compound into liquid containing a compound represented by Formula (1) at the speed of 0.01-05 equivalent/h to generate a ketone represented by Formula (3). Process (B): reacting the specific organometallic compound with the ketone to generate the asymmetric tertiary alcohol expressed by Formula (5). [Formula 1][In the formula, ring Z1 represents a monocyclic or polycyclic non-aromatic group or aromatic ring, and X1 represents halogen atoms, etc.][Formula 2][Formula 3]
Mild N-deacylation of secondary amides by alkylation with organocerium reagents
Wang, Ai-E.,Chang, Zong,Liu, Yong-Peng,Huang, Pei-Qiang
supporting information, p. 1055 - 1058 (2015/09/01)
Secondary amides are a class of highly stable compounds serving as versatile starting materials, intermediates and directing groups (amido groups) in organic synthesis. The direct deacylation of secondary amides to release amines is an important transformation in organic synthesis. Here, we report a protocol for the deacylation of secondary amides and isolation of amines. The method is based on the activation of amides with Tf2O, followed by addition of organocerium reagents, and acidic work-up. The reaction proceeded under mild conditions and afforded the corresponding amines, isolated as their hydrochloride salts, in good yields. In combination with the C-H activation functionalization methodology, the method is applicable to the functionalization of aniline as well as conversion of carboxylic derivatives to functionalized ketones.
Chemoselective synthesis of ketones and ketimines by addition of organometallic reagents to secondary amides
Bechara, William S.,Pelletier, Guillaume,Charette, Andre B.
experimental part, p. 228 - 234 (2012/06/01)
The development of efficient and selective transformations is crucial in synthetic chemistry as it opens new possibilities in the total synthesis of complex molecules. Applying such reactions to the synthesis of ketones is of great importance, as this motif serves as a synthetic handle for the elaboration of numerous organic functionalities. In this context, we report a general and chemoselective method based on an activation/addition sequence on secondary amides allowing the controlled isolation of structurally diverse ketones and ketimines. The generation of a highly electrophilic imidoyl triflate intermediate was found to be pivotal in the observed exceptional functional group tolerance, allowing the facile addition of readily available Grignard and diorganozinc reagents to amides, and avoiding commonly observed over-addition or reduction side reactions. The methodology has been applied to the formal synthesis of analogues of the antineoplastic agent Bexarotene and to the rapid and efficient synthesis of unsymmetrical diketones in a one-pot procedure. Macmillan Publishers Limited. All rights reserved.
Arylation of adamantanamines: II.* Palladium-catalyzed amination of dihalobenzenes with adamantylalkanamines
Averin,Ulanovskaya,Buryak,Savel'ev,Orlinson,Novakov,Beletskaya
experimental part, p. 1790 - 1811 (2011/04/17)
Palladium-catalyzed arylation of various (1-adamantyl)alkanamines with isomeric (ortho, meta, and para) bromochloro-and dibromobenzenes was studied. Optimal catalytic systems were found for the synthesis of mono-and diamination products, and the dependences of their yields on the nature of the initial amine and dihalobenzene and on the amount of base were examined. Side amination products were isolated, and paths of their formation were analyzed. Pleiades Publishing, Ltd., 2010.
Preparation of 1-adamantyl ketones: Structure, mechanism of formation and biological activity of potential by-products
Vicha, Robert,Necas, Marek,Potacek, Milan
, p. 709 - 722 (2008/02/01)
Reactions between adamantane-1-carbonyl chloride and several Grignard reagents as well as interactions with solvents have been examined. Some new and unexpected adamantane derivatives were isolated, fully characterized and their biological activity determined. In particular, an unexpected isochromanone 16 was formed in an SEAr process, in which a stable hydrocarbon was the leaving group.
Influence of catalytic system composition on formation of adamantane containing ketones
Vícha, Robert,Potá?ek, Milan
, p. 83 - 88 (2007/10/03)
The preparation of non-symmetrical ketones by the reaction of acyl chlorides and the corresponding Grignard reagents in the presence of catalytic amounts of metal halides is described. The composition of catalyst has a great influence on the yield of the required ketone as well as on side product formation. For each catalytic system, the yield of ketone and the number of side products changes with the time of addition of the Grignard reagent. We examined the influence of both factors in our model reaction of adamantane-1-carbonyl chloride with ethylmagnesium bromide and discussed the possible mechanisms from this point of view. We have found ZnCl2, MnCl2, AlCl 3 and CuCl to be active catalytic components and developed very efficient, cheap and fast methods for the preparation of alkyl adamantyl ketones. The procedure was also tested for the synthesis of other alkyl aryl ketones. Graphical Abstract.
Evidence that the availability of an allylic hydrogen governs the regioselectivity of the Wacker oxidation
Gaunt,Yu,Spencer
, p. 1844 - 1845 (2007/10/03)
The allylic hydrogen is found to have a dramatic effect on the regioselectivity of the Wacker oxidation, leading to the postulation that an agostic hydrogen or enyl (σ + π) complex helps to stabilise the key intermediate.
The Mechanism of Solvolysis of 2,2-Dimethyl-3-pentyl and 1-(1-Adamantyl)propyl Sulfonates
Shiner Jr., Vernon J.,Neumann, Thomas E.,Basinger, Bradley B.
, p. 1405 - 1420 (2007/10/03)
Solvolysis rates, alpha and beta deuterium isotope rate effects and product yields have been determined for some 1-(1-adamantyl) propyl sulfonate esters, 4, in some ethanol-water, trifluoroethanol-water and hexafluoroisopropyl alcohol-water mixtures. For comparison, similar measurements have been made for solvolysis of 2,2-dimethyl-3-pentyl sulfonates, 5. For the esters 5, the alpha-d and beta-d2 effects vary little with solvent in the ranges of 1.164-1.165 and 1.215-1.241, respectively, and only small yields of unrearranged products are formed; it is concluded that the mechanism involves rate determining formation of the secondary cation-ion pair followed by rapid rearrangement. For the adamantyl analogs, 4, the alpha-d effects vary in the different solvents from 1.162 to 1.213 and the beta-d2 effects vary from 1.339 to 1.649; significant yields of unrearranged and Wagner-Meerwein rearranged (ring expansion) products are formed. The steady state treatment, which had been used previously to fit the results for 1-(1-adamantyl)ethyl esters, was applied to the results for 4; a mechanism which involves partially reversible ionization to the intimate ion-pair followed by competing elimination and solvent separation, to give the substitution products, fits the results reasonably well.
A new route to 3-labeled or 3-substituted 4-homoadamantanones
Takeuchi,Yoshida,Nishida,Kohama,Kitagawa
, p. 37 - 40 (2007/10/02)
The pinacol rearrangement of 3,4-dihydroxyhomoadamantanes containing carbon-13, deuterium, and alkyl, or an aryl subsituent at the C-4 position provides a new route to the title compounds.
