497-67-6Relevant academic research and scientific papers
PROCESSES FOR PREPARING 2-ISOPROPENYL-5-METHYL-4-HEXENOIC ACID, 2-ISOPROPENYL-5-METHYL-4-HEXEN-1-OL, AND A CARBOXYLATE ESTER THEREOF
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Paragraph 0256-0258, (2021/10/22)
The present invention provides a process for preparing 2-isopropenyl-5-methyl-4-hexenoic acid of the following formula (4), comprising steps of: subjecting a Grignard reagent of the following general formula (1), wherein R1 represents a linear, branched, or aromatic monovalent hydrocarbon group having 1 to 8 carbon atoms, and X represents a chlorine atom, a bromine atom, or an iodine atom, and 1,1,1,3,3,3-hexamethyldisilazane to a deprotonation reaction to form a 1,1,1,3,3,3-hexamethyldisilazane derivative; and subjecting 2-methyl-3-buten-2-yl 3-methyl-2-butenoate of the following formula (3) to a rearrangement reaction in the presence of the 1, 1, 1,3,3,3-hexamethyldisilazane derivative to form 2-isopropenyl-5-methyl-4-hexenoic acid (4).
METHOD FOR PRODUCING (E)-2-ISOPROPYL-5-METHYL-2,4-HEXADIENYL ACETATE
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Paragraph 0106-0107, (2015/05/05)
Provided is a simple and efficient method for producing (E)-2-isopropyl-5-methyl-2,4-hexadienyl acetate. More specifically, provided is a method for producing (E)-2-isopropyl-5-methyl-2,4-hexadienyl acetate including the steps of: isomerizing 2-isopropenyl-5-methyl-4-hexenoic acid (1) into (E)-2-isopropyl-5-methyl-2,4-hexadienoic acid (2), reducing thus formed (E)-2-isopropyl-5-methyl-2,4-hexadienoic acid (2) into (E)-2-isopropyl-5-methyl-2,4-hexadienol (3), and acetylating thus formed (E)-2-isopropyl-5-methyl-2,4-hexadienol (3) into (E)-2-isopropyl-5-methyl-2,4-hexadienyl acetate (4), wherein Ac represents an acetyl group.
METHOD FOR PRODUCING 2-ISOPROPYLIDENE-5-METHYL-4-HEXENYL BUTYRATE
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Paragraph 0072-0073, (2015/05/05)
Provided is a simple and efficient method for producing 2-isopropylidene-5-methyl-4-hexenyl butyrate. More specifically, provided is a method for producing 2-isopropylidene-5-methyl-4-hexenyl butyrate, the method including the steps of: isomerizing 2-isopropenyl-5-methyl-4-hexenoic acid ester (1) into 2-isopropylidene-5-methyl-4-hexenoic acid ester (2), reducing thus formed 2-isopropylidene-5-methyl-4-hexenoic acid ester (2) into 2-isopropylidene-5-methyl-4-hexenol (3), and butyrylating thus formed 2-isopropylidene-5-methyl-4-hexenol (3) into 2-isopropylidene-5-methyl-4-hexenyl butyrate (4), wherein R represents a C1-10 hydrocarbon group.
Transition metals in organic synthesis, Part 98.1 Transition metal mediated total synthesis of the potent neuronal cell protecting alkaloid (±)-lavanduquinocin
Froehner, Wolfgang,Reddy, Kethiri R.,Knoelker, Hans-Joachim
, p. 330 - 342 (2013/09/24)
An efficient total synthesis of (±)-lavanduquinocin, a potent neuronal cell protecting alkaloid from Streptomyces viridochromogenes, is reported. Key-steps are an iron-mediated one-pot construction of the carbazole framework and a nickel-mediated coupling reaction. ARKAT-USA, Inc.
Experimental and theoretical investigations for the tandem alkylation-isomerization reactions between unsaturated carboxylic acids and allyl halides
Domingo, Luis R.,Gil, Salvador,Parra, Margarita,Sáez, José A.,Torres, Mercedes
, p. 6233 - 6239 (2007/10/03)
Alkylation of dienediolates from unsaturated carboxylic acids with allylic halides when followed by solventless thermal treatment at 150 to 200°C afford rearranged products on a trend highly dependent on the α carbon substitution. Thus, 2,2-bisallylated acids with H atoms at C-2 lead to its 1,3-shift, whereas 2-methyl-2,2-bisallylated acids lead to the corresponding Cope rearrangement product. In the latter case, this tandem allylation-Cope reaction lead, in a highly regio and diastereoselective way, to products not accessible from direct alkylation. B3LYP/6-31G* energies for the compounds involved at these isomerizations are in reasonable agreement with the experiments, allowing to explain the formation of the more stable product under thermodynamic equilibrations.
Transition metal complexes in organic synthesis, Part 42. First total synthesis of the potent neuronal cell protecting substance (±)- lavanduquinocin via iron- and nickel-mediated coupling reactions
Knoelker, Hans-Joachim,Froehner, Wolfgang
, p. 2537 - 2540 (2007/10/03)
The first total synthesis of the potent neuronal cell protecting alkaloid (±)-lavanduquinocin is described by using an iron-mediated construction of the carbazole skeleton and a nickel-mediated alkylation as the key-steps.
Enantio- and diastereoselective protonation of photodienols: Total synthesis of (R)-(-)-lavandulol
Piva
, p. 7879 - 7883 (2007/10/03)
The total synthesis of (R)-(-)-lavandulol 1 has been achieved by asymmetric protonation of photodienols obtained from the irradiation of prochiral α,β-unsaturated esters. The photodeconjugation of ethyl 5-methyl-2-(1'-methylethylidene)-4-hexenoate (3a), carried out in the presence of catalytic amounts of a β-amino alcohol prepared from (±)-camphor, gives the β,γ-unsaturated isomer 2a in good yields but with moderate enantioselectivities (40% ee). In contrast, irradiation of the corresponding ester 3b, bearing the 1,2:5,6-di-O-isopropylidene-D-glucose group as a chiral alkoxy moiety, affords the deconjugated product 2b in high de (> 95%). Simple reduction of the ester function with LiAlH4 gives (R)-(-)-lavandulol (1) without loss of optical purity.
Synthesis of Some Carboxylic Acid Analogs Cleaved between the C-2 and C-3 Bond of Tetramethylcyclopropanecarboxylic Acid, and Insecticidal Activities of Their Esters
Furuhata, Akimichi,Hirano, Masachika,Fujimoto, Izumi,Matsui, Masano
, p. 1633 - 1640 (2007/10/02)
Carboxylic acids with a cleaved type of cyclopropane ring between the C-2 and C-3 bond in tetramethylcyclopropanecarboxylic acid, the acid part of fenpropathrin, were prepared.Several of their esters with pyrethroidal alcohols exhibited good insecticidal activity, but their activity was a little weaker than that of fenpropathrin.
