37599-63-6Relevant articles and documents
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 (2007)
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.
Direct and selective synthesis of 3-arylphthalides via nickel-catalyzed aryl addition/intramolecular esterification
Qiang, Qing,Liu, Feipeng,Rong, Zi-Qiang
supporting information, (2021/05/10)
Herein we report a nickel-catalyzed aryl addition/intramolecular esterification in a cascade fashion. Under the combination of commercially available nickel precursor and tridentate ligand, the one pot protocol offers a direct, simple and regioselective approach to access 3-aryl phthalide derivatives from two readily available substrates with good efficiency, broad scope as well as satisfactory functional group compatibility.
Rhenium-Catalyzed Phthalide Synthesis from Benzamides and Aldehydes via C-H Bond Activation
Jia, Bing,Yang, Yunhui,Jin, Xiqing,Mao, Guoliang,Wang, Congyang
, p. 6259 - 6263 (2019/09/06)
The [4 + 1] annulation of benzamides and aldehydes for phthalide synthesis was achieved via rhenium-catalyzed C-H activation, which demonstrates an unprecedented reaction pattern distinct from those of other transition-metal catalyses. The reaction also features readily available starting materials, a wide scope for both electro-rich and electro-deficient substrates, and the elimination of homoannulation byproducts.
Introducing the Chiral Transient Directing Group Strategy to Rhodium(III)-Catalyzed Asymmetric C?H Activation
Li, Guozhu,Jiang, Jijun,Xie, Hui,Wang, Jun
, p. 4688 - 4694 (2019/03/17)
The chiral transient directing group (TDG) strategy has been successfully introduced to the rhodium(III)-catalyzed asymmetric C?H activation. In the presence of a catalytic amount of a chiral amine and an achiral rhodium catalyst, various chiral phthalides were synthesized from simple aldehydes with high chemoselectivity, regioselectivity, and enantioselectivity (53 examples, up to 73 % yield and >99 % ee). It is noteworthy that the chiral induction model is different from the previously reported chiral TDG system using amino acid derivatives and palladium salts. The imino group generated in situ from chiral amine and aldehyde acts as the monodentate TDG to promote the C?H activation, stereoselectively generating the chiral rhodacycle bearing a chiral metal center. Moreover, the stereogenic center of the product is created and stereocontrolled during the Grignard-type addition of the C?Rh bond to aldehyde, rather than during the C?H activation step.
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.
Synthesis of phthalide derivatives using nickel-catalyzed cyclization of o-haloesters with aldehydes
Rayabarapu, Dinesh Kumar,Chang, Hong-Tai,Cheng, Chien-Hong
, p. 2991 - 2996 (2007/10/03)
The reaction of o-bromobenzoate (1b) with benzaldehyde (2a) in the presence of [NiBr2(dppe)] (dppe = 1,2-bis(diphenylphosphino)ethane) and zinc powder in THF (24 hours, reflux temperature), afforded 3-phenyl-3H- isobenzofuran-1-one (3a) in an 86% yield. Similarly, o-iodobenzoate reacts with 2a to give 3a, but in a lower yield (50%). A series of substituted aromatic and aliphatic aldehydes (2b, 4-MeC6H4CHO; 2c, 4-MeOC 6H4CHO; 2d, 3-MeOC6H4-CHO 2e, 2-MeOC6H4-CHO; 2f, 4-CNC6H4CHO; 2g, 4-(Me)3-CC6H4CHO; 2h, 4-C6H 4C6H4CHO; 2i, 4-ClC6H 4CHO; 2j, 4-CF3C6H4CHO; 2k, CH 3(CH2)5CHO; 21, CH3(CH 2)2-CHO) also underwent cyclization with o-bromobenzoate (1b) producing the corresponding phthalide derivatives in moderate to excellent yields and with high chemoselectivity. Like 1b, methyl 2-bromo-4,5- dimethoxybenzoate (1c) reacts with tolualdehyde (2b) to give the corresponding substituted phthalide 3m in a 71% yield. The methodology can be further applied to the synthesis of six-membered lactones. The reaction of methyl 2-(2-bromophenyl)acetate (1d) with benzaldehyde under similar reaction conditions afforded six-membered lactone 3o in a 68% yield. A possible catalytic mechanism for this cyclization is also proposed.
