1122-24-3Relevant academic research and scientific papers
α-Branched Ketone Dienolates: Base-Catalysed Generation and Regio- and Enantioselective Addition Reactions
Urruzuno, I?aki,Mugica, Odei,Zanella, Giovanna,Vera, Silvia,Gómez-Bengoa, Enrique,Oiarbide, Mikel,Palomo, Claudio
supporting information, p. 9701 - 9709 (2019/07/12)
In this study, the unique capacity of bifunctional Br?nsted bases to generate α-branched ketone dienolates and control both site- and stereoselectivity of their addition reactions to representative classes of carbon electrophiles (i.e., vinyl sulfones, nitroolefins, formaldehyde) is documented. We demonstrate that by using selected chiral tertiary amine/squaramide catalysts, the reactions of β,γ-unsaturated cycloalkanones proceed through the dienolate Cα almost exclusively and provide all-carbon quaternary cyclic ketone adducts in good yields with very high enantioselectivities. A minor amount (5 %) of γ-addition is observed when nitroolefins are used as electrophiles. The parent acyclic ketone dienolates proved to be less reactive under these conditions, and thus still constitute a challenging class of substrates. Quantum chemical calculations correctly predict these differences in reactivity and explain the observed site-specificity and enantioselectivity.
Pd(OAc)2/P(cC6H11) 3-catalyzed allylation of aryl halides with homoallyl alcohols via retro-allylation
Iwasaki, Masayuki,Hayashi, Sayuri,Hirano, Koji,Yorimitsu, Hideki,Oshima, Koichiro
, p. 4463 - 4469 (2008/02/04)
Allylations of aryl halides take place upon treatment of tertiary homoallyl alcohols with aryl halides in the presence of cesium carbonate and a palladium catalyst. The allylation reaction would consist of the following steps: (1) oxidative addition of ar
Gold-catalyzed synthesis of substituted tetrahydronaphthalenes
Grise, Christiane M.,Barriault, Louis
, p. 5905 - 5908 (2007/10/03)
(Diagram presented) We report a gold-catalyzed benzannulation of 3-hydroxy-1,5-enynes to generate tetrahydronaphthalenes. This mild process proves to be an effective method to synthesize various metasubstituted aromatic rings in good yields.
Cyclic amidino agents useful as nitric oxide synthase inhibitors
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, (2008/06/13)
The current invention discloses useful amidino derivative useful as nitric oxide synthase inhibitors.
Azepine derivatives useful as nitric oxide synthase inhibitors
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, (2008/06/13)
The current invention discloses azepine derivatives useful as nitric oxide synthase inhibitors.
Free radical mediated ring expansion of vinyl epoxides
Kim,Lee
, p. 6575 - 6578 (2007/10/02)
Free radical mediated ring expansion of vinyl epoxides occurred smoothly via n-Bu3Sn or PhS radical addition to vinyl epoxides, epoxide fragmentation, β-cleavage of alkoxy radicals, cyclization, and elimination.
Vinylation of cyclohexanone enolates using vinyl ether-iron complexes. Diastereoselectivity of carbon-carbon bond formation
Chang, Tony C. T.,Coolbaugh, Thomas S.,Foxman, Bruce M.,Rosenblum, Myron,Simms,Stockman
, p. 2394 - 2404 (2008/10/08)
Cationic vinyl ether-iron complexes 1, isolated as stable BF4- salts, are readily available from α-halo acetals and ketals. The olefin ligand in these complexes is unsymmetrically bound to the metal, which accounts for the relatively low barrier for rotation about the formal double bond, which is observed in these substances (15-23 kcal/mol), and for the high regioselectivity with which nucleophiles add to the activated olefinic center. The salts 1 serve as vinylating, isopropenylating, and cis-propenylating reagents with cyclohexanone enolates. Reaction of 1a with cyclohexanone enolate gave a single diastereomeric product 5. This has been converted to the lactone 10, which establishes the relative configuration of the adjacent chiral centers in 5. The relative configuration of analogous chiral centers in the major diastereomer 16a, formed by the alkylation of 3-methylcyclohexanone enolate with 1a, has been established by a single-crystal X-ray diffraction study and shown to be identical with that in 5. Complex 1a also gives a single diastereoisomeric adduct with 6-methylcyclohexanone enolate, and this has been shown by 13C NMR studies to have the same relative configuration at the newly formed chiral centers as in 5 and 16a. Alkylation of 5-methylcyclohexanone enolate with 1b leads to a mixture of isopulegone and isoisopulegone, while alkylation of the kinetic enolate derived from 3-methyl-2-cyclohexenone with this complex yields isopiperitenone.
