23068-91-9Relevant articles and documents
OZONOLYTIC CLEAVAGE OF CYCLOALKENES TO TERMINALLY DIFFERENTIATED PRODUCTS
Schreiber, Stuart L.,Claus, Ronald E.,Reagan, Jeff
, p. 3867 - 3870 (1982)
Conditions are reported which convert cycloalkenes to terminally differentiated product through the intermediacy of α-alkoxy hydroperoxides.
MECHANISTIC AND SYNTHETIC ASPECTS OF THE ACID-CATALYSED HYDROLYSIS OF 2,2-DIMETHOXY-3,4-DIHYDROPYRANS INTO 3,4-DIHYDRO-α-PYRONES AND δ-KETO ESTERS
Scheeren, J. W.,Bakker, C. G.,Peperzak, R.,Nivard, R. J. F.
, p. 1821 - 1824 (1987)
Acid-catalysed hydrolysis of 2,2-dimethoxy-3,4-dihydropyrans (1) yields mixtures of δ-keto esters (2) and 3,4-dihydro-α-pyrones (3).The amount of 3 increases with increasing alkyl substitution in the 3-, 5- and 6-position of 1 and when the hydrolysis is carried out in a two-phases system of water/dichloromethane.It is shown that 3 is formed directly from 1 whereas 2 is formed directly from 1 and by methanolysis of 3.The mechanistic and synthetic aspects of these hydrolysis reactions are discussed.
Ozonolysis of 3-caren-5-one
Galin,Kukovinets,Zainullin,Shershovets,Kashina,Akhmetov,Kunakova,Tolstikov
, p. 238 - 242 (2001)
Cleavage by ozonolysis of a cyclic unsaturated ketone, 3-caren-5-one, was investigated under different conditions. The main reaction product is ketocaronic acid. A scheme of ketocaronic acid formation was suggested basing on kinetics of ozone reaction with 3-caren-5-one and thermal decomposition of peroxides.
Oxidation of 2-substituted cycloalkanones with cerium(IV) sulfate tetrahydrate in alcohols and acetic acid
He, Liangyou,Horiuchi, C. Akira
, p. 2515 - 2521 (2007/10/03)
The reaction of 2-substituted cycloalkanones with cerium(IV) sulfate tetrahydrate (CS) in alcohols and acetic acid gave the corresponding alkyl esters of oxo acids (80-96%) and oxo acids (78-96%), respectively, by oxidative cleavage of the C(R).C=O bond. In the case of 2-iodocycloalkanones in methanol, the dimethyl ester was obtained in good yield. A treatment of 5α-cholestan-3-one with CS in methanol produced 2-acetal 3-ester of 2,3-seco derivative in good yield. The effects of cerium(IV) and copper(II) salts are also discussed.
Dehydrooligopeptides. XVI. Convenient syntheses of two kinds of antrimycins Av and Dv containing dehydrovaline residues
Nakamura,Ito,Shin
, p. 2151 - 2161 (2007/10/02)
Eight kinds of peptide antibiotics, antrimycins (1), consist of four sorts of unusual α-amino acids, that is, hydroxymethylserine, (2S,3S)-2,3-diaminobutanoic acid, (S)-2,3,4,5-tetrahydro-3-pyridazinecarboxylic acid, and dehydrovaline (ΔVal) or (E)-dehydr
Useful Syntheses of (3S)-2,3,4,5-Tetrahydropyridazine-3-carboxylic Acid and Its Dehydrotetrapeptide Derivatives
Nakamura, Yutaka,Shin, Chung-gi
, p. 1953 - 1956 (2007/10/02)
The stereoselective synthesis of (3S)-2,3,4,5-tetrahydropyridazine-3-carboxylic acid (Pya), which is a cyclic α-amino acid at center of antrimycins (1), was successful.Moreover, the synthesis of the C-terminal dehydrotetrapeptide of 1 containing Pya residue at N-terminus is described.
Ozonolysis of Symmetrically 1,2-Disubstituted Ethylenes in HCl/Methanol Solutions: Acid Catalyzed Reactions of Primary Cleavage Products
Griesbaum, Karl,Neumeister, Joachim
, p. 2697 - 2706 (2007/10/02)
The ozonolysis of olefins in 1 M anhydrous solutions of hydrogen chloride in methanol at /= 0 deg C was investigated.Upon warm-up of the ozonolysis products, the peroxidic primary fragmentation products were converted into non peroxidic end-products by HCl-catalyzed reactions.Cyclopentene (1a) and cyclohexene (1b), e.g., afforded mixtures of the corresponding α,ω-dialdehydebis(dimethyl acetals) (8), dimethyl α,ω-dicarboxylates (9), and methyl ω-aldehyde dimethyl acetal carboxylates (10).Norbornene (1c) gave a mixture of the correspondingly substituted 1,3-cyclopentane compounds (8c - 10c), phenanthrene (22) gave a mixture of methyl 2'-formyl-2-biphenylcarboxylate (24a), 2,2'-biphenyldicarbaldehyde (24b), and dimethyl 2,2'-biphenyldicarboxylate (24c).A reaction scheme was advanced for the rationalization of the types and the distribution of the products.It was partly substantiated by model reactions.