- PROCESSES FOR CONVERSION OF BIOLOGICALLY DERIVED MEVALONIC ACID
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The invention relates to a process comprising reacting mevalonic acid, or a solution comprising mevalonic acid, to yield a first product or first product mixture, optionally in the presence of a solid catalyst and/or at elevated temperature and/or pressure. The invention further relates to a process comprising: (a) providing a microbial organism that expresses a biosynthetic mevalonic acid pathway; (b) growing the microbial organism in fermentation medium comprising suitable carbon substrates, whereby biobased mevalonic acid is produced; and (c) reacting said biobased mevalonic acid to yield a first product or first product mixture.
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Paragraph 0107-0111
(2016/06/13)
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- Oxidative Ring-Opening Reaction of Cyclopropanone Acetals with Carbonyl Compounds via Photoinduced Electron Transfer. Generation of a β-Carbonyl Radical Species and Its Application to the Synthesis of γ-Hydroxy Ester Derivatives
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Photoinduced electron transfer (PET) reactions of 2-substituted or 2,2-disubstituted cyclopropanone methyl trialkylsilyl acetals 1a-e,g and 1-siloxy-2-oxabicyclohexane (1f) with carbonyl compounds 2 (benzophenone (2a), acetophenone (2b), 2-acetonaphthone (2c), 2-acetylpyridine (2d), 4-acetylbenzonitrile (2e), 2,3-butanedione (2f), and benzoyl cyanide (2g)) were examined in the presence of Mg(ClO4)2.Carbon-carbon bond coupling products (γ-hydroxy esters 3 or their derivative butyrolactones 4) between 1 and 2 were formed in good yields.A mechanism is proposed for the product formation which is initiated by the single electron transfer (SET) from 1 to the excited state of 2.The set generates a transient pair of ion radicals, i.e. a ring-opened sec- or tert-β-carbonyl radical from 1 and a ketyl radical ion from 2 stabilized by the Mg salt.This realizes a novel type of carbon-carbon bond formation at the sterically crowded β-position of propanoates.
- Abe, Manabu,Oku, Akira
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p. 3065 - 3073
(2007/10/02)
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- Reinvestigation of a Synthesis of (R,S)-Mevalonolactone
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An n.m.r. study of the reaction of 3-hydroxy-3-methylpentane-1,5-dioic acid (5) with excess of acetic anhydride is described.It has shown that 3-hydroxy-3-methylpentane-1,5-dioic acid anhydride (2), previously described by Scott and Shishido as an intermediate in their synthesis of mevalonolactone, is formed only transiently, along with 3-acetoxy-3-methylpentane-1,5-dioic acid (6).Both intermediates eventually give 3-acetoxy-3-methylpentane-1,5-dioic acid anhydride (3).To obtain (R,S)-mevalonolactone, sodium borohydride reduction of 3-hydroxy-3-methylpentane-1,5-dioic acid anhydride (2), prepared from the diacid (5) and N,N-dicyclohexylcarbodi-imide, is shown to be better than reduction of 3-acetoxy-3-methylpentane-1,5-dioic acid anhydride (3).
- Lewer, Paul,MacMillan, Jake
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p. 1417 - 1420
(2007/10/02)
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