72424-08-9Relevant academic research and scientific papers
Visible Light-Promoted Magnesium, Iron, and Nickel Catalysis Enabling C(sp3)-H Lactonization of 2-Alkylbenzoic Acids
Li, Sasa,Su, Mincong,Sun, Jie,Hu, Kunjun,Jin, Jian
supporting information, p. 5842 - 5847 (2021/07/31)
A mild and practical C(sp3)-H lactonization protocol has been achieved by merging photocatalysis and magnesium (iron, nickel) catalysis. A diverse range of 2-alkylbenzoic acids with a variety of substitution patterns could be transformed into the corresponding phthalide products. Based on the mechanistic experimentation and reported prior studies, a possible mechanism for the benzylic oxidative lactonization reaction was proposed with the hypothetic photoactive ternary complex formed between the 2-alkylbenzoic acid substrate, magnesium ion, and bromate anion.
Saturated oxygen and nitrogen heterocycles: Via oxidative coupling of alkyltrifluoroborates with alkenols, alkenoic acids and protected alkenylamines
Shikora, Jonathan M.,Um, Chanchamnan,Khoder, Zainab M.,Chemler, Sherry R.
, p. 9265 - 9269 (2019/10/22)
Saturated heterocycles are important components of many bioactive compounds. The method disclosed herein enables a general route to a range of 5-, 6- and 7-membered oxygen and nitrogen heterocycles by coupling potassium alkyltrifluoroborates with heteroat
Palladium-Catalyzed Direct Oxidative Coupling of Iodoarenes with Primary Alcohols Leading to Ketones: Application to the Synthesis of Benzofuranones and Indenones
Suchand, Basuli,Sreenivasulu, Chinnabattigalla,Satyanarayana, Gedu
, p. 4832 - 4843 (2019/07/31)
In the present study, a palladium-catalyzed direct oxidative acylation through cross-dehydrogenative coupling has been investigated, utilizing readily available primary alcohols as acylating sources. Overall, this oxidative coupling proceeds via three distinct transformations such as oxidation, radical formation, and cross-coupling in one catalytic process. This protocol does not involve the assistance of a directing group or activation of the carbonyl group by any other means. Furthermore, this reaction made use of no toxic CO gas as carbonylating agent; instead, feedstock primary alcohols have been utilized as acylation source. Notably, the synthesis of benzofuranones and indenones is enabled. This strategy was also applied to the synthesis of n-butylphthalide, fenofibrate, pitofenone, and neo-lignan.
Synthesis of 1,2-phenylenedimethanols by base-promoted reduction of isobenzofuran-1(3H)-ones with silane
Liu, Bin,Zhou, Xigeng
supporting information, p. 725 - 728 (2018/12/11)
An efficient method for preparation of substituted 1,2-phenylenedimethanols and aliphatic 1,4-diols that are valuable intermediates in organic synthesis, has been developed by the base-promoted reduction of isobenzofuran-1(3H)-ones and γ-lactones with silane under mild conditions. Compared with traditional procedures using stoichiometric amounts of metal hydrides and alkyl reductants, the present method avoids the use of sensitive reagents and is operationally simple and a broad variety of functional groups are tolerated.
Electron-Transfer-Induced Intramolecular Heck Carbonylation Reactions Leading to Benzolactones and Benzolactams
Fukuyama, Takahide,Bando, Takanobu,Ryu, Ilhyong
supporting information, p. 3015 - 3021 (2018/06/08)
A metal-catalyst-free intramolecular Heck carbonylation reaction of benzyl alcohols and benzyl amines with carbon monoxide under heating at 250 °C affords the corresponding benzolactones and benzolactams in good to excellent yields. A hybrid radical/ionic chain mechanism, involving electron transfer from radical anions generated by nucleophilic attack of alcohols or amines on intermediate acyl radicals, is proposed.
Ruthenium-Catalyzed Enantioselective Hydrogenation/Lactonization of 2-Acylarylcarboxylates: Direct Access to Chiral 3-Substituted Phthalides
Lu, Bin,Zhao, Mengmeng,Ding, Guangni,Xie, Xiaomin,Jiang, Lili,Ratovelomanana-Vidal, Virginie,Zhang, Zhaoguo
, p. 3989 - 3996 (2017/09/13)
Highly enantioselective tandem hydrogenation/lactonization of various 2-acylarylcarboxylates including 2-aroylarylcarboxylates were realized by using [RuCl(benzene)(S)-SunPhos]Cl as the catalyst under mild reaction conditions. Excellent enantioselectivities (up to 99.6 % ee) and activities (S/C=1000) were obtained. This convenient and practical method enables a direct access to a series of highly optically pure 3-substituted phthalides that are very important molecules as valuable pharmacological compounds and diversified synthons for medicinal chemistry. Moreover, a gram-scale reaction was performed to further demonstrate the practicality of this approach.
Domino [Pd]-Catalysis: One-Pot Synthesis of Isobenzofuran-1(3H)-ones
Mahendar, Lodi,Satyanarayana, Gedu
, p. 7685 - 7691 (2016/09/09)
An efficient domino [Pd]-catalysis for the synthesis of isobenzofuran-1(3H)-ones is presented. The strategy shows broad substrate scope and is amenable to o-bromobenzyl tertiary/secondary/primary alcohols. Significantly, the method was applied to the synthesis of antiplatelet drug n-butyl phthalide and cytotoxic agonist 3a-[4′-methoxylbenzyl]-5,7-dimethoxyphthalide.
Cu-MEDIATED ANNULATION FOR THE EFFECTIVE SYNTHESIS OF 3-SUBSTITUTED PHTHALIDES
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Page/Page column 0072; 0116; 0117, (2015/02/25)
The present invention disclosed herein is a novel commercially feasible, one pot synthesis of library of 3-substituted phthalides of formula I via CuCN mediated oxidative cyclization in high yield. Formula I
Cu-MEDIATED ANNULATION FOR THE EFFECTIVE SYNTHESIS OF 3-SUBSTITUTED PHTHALIDES
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Page/Page column 20, (2013/07/19)
The present invention disclosed herein is a novel commercially feasible, one pot synthesis of library of 3-substituted phthalides of formula I via CuCN mediated oxidative cyclization in high yield. Formula I
Highly efficient cyclization of o-iodobenzoates with aldehydes catalyzed by cobalt bidentate phosphine complexes: A novel entry to chiral phthalides
Chang, Hong-Tai,Jeganmohan, Masilamani,Cheng, Chien-Hong
, p. 4356 - 4363 (2008/02/05)
Methyl 2-iodobenzoates 1a-c undergo cyclization reactions with various aromatic aldehydes 2a-m (RC6CHO: R = H 2a, 4-CH3, 2b, 4tBu 2c, 4-OMe 2d, 3-OMe 2e, 4-C1 2f, 4-CF3 2g, 4-CN 2h, 4-Ph 2i; benzo [d][1,3]dioxole-5-carbaldehyde (2j), 1napthaldehyde (2k), benzofuran-2- carbaldehyde (21), and isonicotinaldehyde (2m)) in the presence of [CoI2(dppe)] (dppe = l,2-bis(diphenylphosphino)ethane) and Zn powder in dry THF at 75 °C for 24 h to give the corresponding phthalide derivatives 3a-m and 3q-t in good to excellent yields. Under similar reaction conditions, less reactive aliphatic aldehydes, heptanal (2n), butyraldehyde (2o), and 2-phenylacetaldehyde (2p) also underwent cyclization reactions with la to provide 3n-p, respectively, in fair to good yields. The catalytic reaction can be further extended to cinnamyl aldehyde (2q) with la to give the corresponding phthalide derivative 3u. This synthetic method is compatible with a variety of functional groups on the aryl ring of 2. The high efficiency of the cobalt catalyst containing a dppe (dppe = l,2-bis(diphenylphosphino)ethane) ligand encouraged us to investigate the asymmetric version of the present catalytic reaction by employing bidentate chiral ligands. Thus, aromatic aldehydes 2a-c, 2f, and 2 g undergo cyclization with 2-iodobenzoate (la) smoothly in the presence of [CoI2{(S,S)- dipamp}] ((S,S)-dipamp = (1S,2S)-(+)-bis[2-methoxyphenyl]phenylphosphino)ethane) and zinc powder in THF at 75 °C for 24 h, giving the corresponding (S)-phthalides 4a-e in 8189 % yields with 70-98 % ee. A possible mechanism for the present catalytic reaction is proposed.
