131407-57-3Relevant academic research and scientific papers
Concise total synthesis of 9-methoxystrobilurin A
Uchiro, Hiromi,Nagasawa, Koh,Aiba, Yasuyuki,Kobayashi, Susumu
, p. 4165 - 4168 (2007/10/03)
Total synthesis of a potent antifungal and cytostatic 9- methoxystrobilurin A was achieved by developing a concise and general route to β-methoxy acrylate. (C) 2000 Elsevier Science Ltd.
Formation of Vinylcyclopropane and Cyclopentene Derivatives from Alkenyl-Substituted Chromium Carbene Complexes: Competition between Formal and Cycloadditions
Wienand, Anette,Reissig, Hans-Ulrich
, p. 957 - 965 (2007/10/02)
The alkenyl-substituted chromium carbene complexes 1 - 4 were synthesized following the method of Aumann which starts from the corresponding aldehydes.At 80 deg C the styryl-substituted complex 1 and electron-deficient olefins smoothly provide vinylcyclopropane derivatives 6, 8, 10, and 12 in good yields.On the other hand, methyl acrylate and the anisyl- and furyl-substituted vinylcarbene complexes 2 and 3 give mixtures of the expected vinylcyclopropanes and of cyclopentene derivatives.The pyrrolyl-substituted complex 4 and methyl acrylate exclusively afford the cyclopentenes 24a/b which are the result of a hitherto unprecedented formal cycloaddition of the vinylcarbene complex to the olefin.However, there are strong arguments suggesting the corresponding vinylcyclopropanes as intermediates.The very smooth vinylcyclopropane -> cyclopentene rearrangement probably occurs via zwitterionic intermediates that are well-stabilized by donor and acceptor substituents.Hydrolysis of 24a/b to the cyclopentanone derivatives 25a/b demonstrates that this new route to five-membered carbocycles should have synthetic potential.
Stereoselective Reduction of γ-Oxobutanoic Acids Using DIBAL-H and ZnCl2
Frenette, R.,Monette, M.,Bernstein, M. A.,Young, R. N.,Verhoeven, T. R.
, p. 3083 - 3089 (2007/10/02)
A variety of γ-aromatic γ-ketobutanoic acids can be reduced selectively, under optimized conditions, by the use of DIBAL-H and ZnCl2 to provide the (RS,SR)-γ-aryl-γ-hydroxy-β-methylbutanoic acids.Further evidence has been gathered to support the hypothesis that the reaction proceeds by formation of a seven-membered ring complex with the aluminium or zinc atom bridging the ketone and carboxyl groups which preceeds the reduction step and that this templated reduction accounts for observed high diastereoselectivity.Also we have shown that some γ-aryl-γ-butyrolactones can be easily transformed via an oxidative cleavage of the aromatic ring to provide selective synthesis of either cis- or trans-tetrahydro-3-methyl-5-oxo-2-furancarboxylic acid derivatives.
