29652-82-2Relevant articles and documents
Green and simple preparation process of alpha-asarone
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Paragraph 0044; 0048-0050; 0054; 0058-0060, (2019/10/01)
The invention relates to the technical field of medicine, in particular to a green and simple preparation process of alpha-asarone. 1,2,4-trimethoxybenzene is adopted as a raw material, and three steps, namely, an acylation reaction, a reduction reaction and a dehydration reaction are included. Through the preparation process of alpha-asarone, the total yield can reach 62.3% or above, all organicsolvents can be recycled repeatedly, and the process has the advantages of low cost, small pollution, safe and convenient operation, high yield and the like.
Asymmetric Oxidation of Enol Derivatives to α-Alkoxy Carbonyls Using Iminium Salt Catalysts: A Synthetic and Computational Study
Page, Philip C. Bulman,Almutairi, Saud M.,Chan, Yohan,Stephenson, G. Richard,Gama, Yannick,Goodyear, Ross L.,Douteau, Alice,Allin, Steven M.,Jones, Garth A.
, p. 544 - 559 (2019/01/11)
We report herein the first examples of asymmetric oxidation of enol ether and ester substrates using iminium salt organocatalysis, affording moderate to excellent enantioselectivities of up to 98% ee for tetralone-derived substrates in the α-hydroxyketone products. A comprehensive density functional theory study was undertaken to interpret the competing diastereoisomeric transition states in this example in order to identify the origins of enantioselectivity. The calculations, performed at the B3LYP/6-31G(D) level of theory, gave good agreement with the experimental results, in terms of the magnitude of the effects under the specified reaction conditions, and in terms of the preferential formation of the (R)-enantiomer. Just one of the 30 characterized transition states dominates the enantioselectivity, which is attributed to the adoption of an orientation relative to stereochemical features of the chiral controlling element that combines a CH interaction between a CH2 group in the substrate and one of the aromatic rings of the biaryl section of the chiral auxiliary with a good alignment of the acetoxy group with the other biaryl ring, and places the smallest substituent on the alkene (a hydrogen atom) in the most sterically hindered position.
Short Enantioselective Total Synthesis of Tatanan A and 3-epi-Tatanan A Using Assembly-Line Synthesis
Noble, Adam,Roesner, Stefan,Aggarwal, Varinder K.
supporting information, p. 15920 - 15924 (2016/12/16)
Short and highly stereoselective total syntheses of the sesquilignan natural product tatanan A and its C3 epimer are described. An assembly-line synthesis approach, using iterative lithiation–borylation reactions, was applied to install the three contiguo
Unexpected formation of aryl dialkyl carbinol as a side product from the reaction of methoxyarylaldehydes with Grignard reagents
Sharma, Anuj,Joshi, Bhupendra P.,Singh, Narendra P.,Sinha, Arun K.
, p. 847 - 851 (2007/10/03)
In the attempted formation of secondary aryl alkyl carbinols from the reaction of methoxyarylaldehydes with Grignard reagents, aryl dialkyl carbinols were formed as unexpected side products. A mechanism for their formation is proposed.
An effective system to synthesize hypolipidemic active α-asarone and related methoxylated (E)-arylalkenes
Sharma, Anuj,Joshi, Bhupendra P.,Sinha, Arun K.
, p. 2231 - 2235 (2007/10/03)
Methoxylated (E)-arylalkenes (1a-1k) were prepared in two steps by an improved Grignard reaction comprising the reverse addition of alkylmagnesium bromide to benzaldehydes (2a-2k) in anhydrous ether and toluene into arylalkanols (3a-3k) in high yield, followed by dehydration with silica gel under microwave irradiation for 3-12 min, depending upon the substituents attached to the aromatic ring to afford hypolipidemic active α-asarone (1a) and related methoxylated (E)-arylalkenes (1b-1k).
Process for the preparation of pharmacologically active α-asarone from toxic β-asarone rich acorus calamus oil
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, (2008/06/13)
The present invention relates to a process for the preparation of high purity and yield α-asarone, trans 2,4,5-trimethoxy cinnamaldehyde, 2,4,5-trimethoxy-phenyl propionone, from β-asarone or β-asarone rich Acorus calamus oil containing α and γ-asarone by hydrogenating, followed by treatment with DDQ with or without solid support of silica gel or alumina in dry organic solvent and α-asarone can also be obtained by treating the hydrogenated product of β-asarone or β-asarone rich Acorus calamus with DDQ in an aqueous organic solvent to obtain an intermediate 2,4,5-trimethoxy phenyl propionone, which in turn is reduced with sodiumborohydride to obtain the corresponding 2,4,5-trimethoxy-phenyl propanol and followed by final treatment with a dehydrating agent.
A PROCESS FOR THE PREPARATION OF PHARMACOLOGICALLY ACTIVE ALPHA-ASARONE FROM TOXIC BETA-ASARONE RICH ACORUS CALAMUS OIL
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Page/Page column 23, (2008/06/13)
The present invention relates to a process for the preparation of high purity and yield α-asarone, trans 2,4,5-trimethoxy cinnamaldehyde, 2,4,5-trimethoxy-phenyl propionone, from β-asarone or β-asarone rich Acorus calamus oil containing α and γ-asarone by hydrogenating, followed by treatment with DDQ with or without solid support of silica gel or alumina in dry organic solvent and α-asarone can also be obtained by treating the hydrogenated product of β-asarone or β-asarone rich Acorus calamus with DDQ in an aqueous organic solvent to obtain an intermediate 2,4,5-trimethoxy phenyl propionone, which in turn is reduced with sodiumborohydride to obtain the corresponding 2,4,5-trimethoxy-phenyl propanol and followed by final treatment with a dehydrating agent.
