1540-94-9Relevant articles and documents
PRODUCTION OF TWO ESTERS USING HOMOGENEOUS CATALYST
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Paragraph 0051, (2016/10/31)
Disclosed is a process for preparing two esters by reacting an aldehyde with an alcohol in the presence of a ruthenium complex compound as a catalyst. The process is particularly useful for preparing ethyl acetate and n-butyl acetate, isobutyl acetate, or 2-ethylhexyl acetate in high yield by coupling acetaldehyde with n-butanol, i-butanol, or 2-ethylhexanol.
Microwave-assisted efficient one-step synthesis of amides from ketones and benzoxazoles from (2-hydroxyaryl) ketones with acetohydroxamic acid using sulfuric acid as the catalyst
Madabhushi, Sridhar,Chinthala, Narsaiah,Vangipuram, Venkata Sairam,Godala, Kondal Reddy,Jillella, Raveendra,Mallu, Kishore Kumar Reddy,Beeram, China Ramanaiah
experimental part, p. 6103 - 6107 (2011/11/30)
Efficient one-step method for the synthesis of amides directly from ketones and benzoxazoles from (2-hydroxyaryl) ketones by the reaction of acetohydroxamic acid using sulfuric acid as catalyst was described.
Silica sulfuric acid as a reusable catalyst for the conversion of ketones into amides by a Schmidt reaction under solvent-free conditions
Eshghi, Hossein,Hassankhani, Asadollah,Mosaddegh, Elaheh
, p. 218 - 219 (2007/10/03)
Silica sulfuric acid is a highly efficient reagent for the conversion of a variety of ketones into the corresponding amides by a Schmidt reaction under solvent-free conditions. Cyclic, aliphatic and aromatic ketones with electron-donating or withdrawing substituents may be converted easily in excellent yield. The major advantages of this method are: operational simplicity, the ready availability of the reagent, selectivity, general applicability, mild reaction conditions, short reaction times and high yields. The recovered catalyst could be used in new attempts without any purification.
Stereoselective synthesis of 2-aminocyclobutanols via photocyclization of α-amido alkylaryl ketones: Mechanistic implications for the Norrish/Yang reaction
Griesbeck, Axel G.,Heckroth, Heike
, p. 396 - 403 (2007/10/03)
A series of chiral N-acylated α-amino p-methylbutyrophenone derivatives 1a-1h was synthesized from α-amino acids via a three-step procedure. These substrates were photolyzed in benzene and gave Norrish II and Norrish I cleavage products as well as the N-acylated 2-aminocyclobutanols that derive from γ-hydrogen abstraction and 1,4-triplet biradical combination (Yang cyclization). The products were formed with characteristic Yang/cleavage ratios. The quantum yields for the photodecomposition of the N-acetyl-protected substrates 1b,e,f were moderate (12-26%); the diastereoselectivities of the cyclobutanol formation were remarkably high for all substrates. High diastereospecificity was observed for the isoleucine derivatives (2S,3S)-1g and allo-(2S,3R)-1g; the Yang reaction dominated the photochemistry of allo-1g, whereas 1g gave preferentially Norrish II cleavage. The role of hydrogen bonding as one of the stereo-directing effects was demonstrated by comparison of the cyclization efficiency of the valine derivative 1e with 1h,i,j. Also, aromatic β-keto esters gave the Yang cyclization products in low yields. The diastereoselectivity of the cyclobutanol formation was rationalized by a three-step mechanism where every step is connected with one distinct stereochemical induction mechanism: (a) diastereoselective hydrogen abstraction, (b) conformational equilibration of the 1,4-tetramethylene biradicals (as calculated by semiempiric methods) controlled by hydrogen bonding, and (c) diastereoselective biradical combination (versus cleavage) influenced by spin-orbit coupling controlled intersystem crossing geometries.
OXIDATION-REDUCTION MECHANISMS - INNER-SPHERE AND OUTER-SPHERE ELECTRON TRANSFER IN THE REDUCTION OF IRON(III), RUTHENIUM(III), AND OSMIUM(III) COMPLEXES BY ALKYL RADICALS. MECHANISMS -
Rollick,Kochi
, p. 1319 - 1330 (2007/10/02)
Alkyl radicals are readily oxidized by the tris(phenanthroline) and tris(bipyridine) complexes ML//3**3** plus of iron(III), ruthenium(III), and osmium(III) in acetonitrile solution, the second-order rate constants easily exceeding 10**6 M** minus **1s** minus **1 at 25 degree C. Two oxidative processes are identified as (a) ligand substitution on the coordinated 1,10-phenanthroline to yield various alkylphenanthrolines and (b) cation formation to afford alkenes and N-alkylacetamides (after hydrolysis). Cation formation is characterized by extensive skeletal rearrangement of neopentyl, isobutyl, and n-propyl groups, whereas ligand substitution by the same alkyl radicals occurs without any rearrangement.
The Effect of Electrochemically Generated Positive Bromine Species in Acetonitrile on the Cleavage of C-Br and C-Cl Bonds.
Becker, James Y.,Zemach, Dvora
, p. 336 - 340 (2007/10/02)
The fate of bromine formed from C-Br cleavage during the course of anodic oxidation of alkyl bromides in acetonitrile on platinum has been investigated potentiostatically.It is suggested that positive bromine species are formed and they are potentially reactive towards alkyl bromides, yielding similar products to those obtained by direct anodic oxidation of the same bromides.Furthermore, whereas alkyl chlorides do not undergo C-Cl fission by direct anodic oxidation it is shown that positive bromine species are energetically sufficient to break C-Cl bonds, although not very efficiently.We suggest that a possible structure for the complex between acetonitrile and positive bromine species is mainly +Br3- and the mechanism for its formation is discussed.The spectrum of this species found identical to that of Br3- (269 nm) in acetonitrile.
