43020-10-6Relevant academic research and scientific papers
Photocatalytic synthesis of tetra-substituted furans promoted by carbon dioxide
K?nig, Burkhard,Ritu,Tian, Ya-Ming,Wang, Huaiju
, p. 241 - 246 (2022/01/06)
We report a simple protocol for the transition metal-free, visible-light-driven conversion of 1,3-diketones to tetra-substituted furan skeleton compounds in carbon dioxide (CO2) atmosphere under mild conditions. It was found that CO2could be incorporated at the diketone enolic OH position, which was key to enabling the cleavage of a C-O bond during the rearrangement of a cyclopropane intermediate. This method allows for the same-pot construction of two isomers of the high-value tetra-substituted furan scaffold. The synthetic scope and preliminary mechanistic investigations are presented.
Auto-Tandem Catalysis-Induced Synthesis of Trisubstituted Furans through Domino Acid-Acid-Catalyzed Reaction of Aliphatic Aldehydes and 1,3-Dicarbonyl Compounds by using N-Bromosuccinimide as Oxidant
Huang, Wenbo,Liu, Changhui,Gu, Yanlong
supporting information, p. 1811 - 1818 (2017/06/09)
A simple aluminium(III) chloride-catalyzed synthesis of tri-substituted furans from aliphatic aldehydes and 1,3-dicarbonyl compounds was developed by using N-bromosuccinimide (NBS) as an oxidant. This method was effective for the synthesis of various furan derivatives. Some of the products were not accessible with the previously reported methods. Mechanically, this reaction involved an auto-tandem catalysis based on a newly reported acid-acid-catalyzed tandem reaction to ensure that furans were successfully synthesized. (Figure presented.).
Cobalt(II)-catalyzed electrophilic alkynylation of 1,3-dicarbonyl compounds to form polysubstituted furans via π-π Activation
Roslan, Irwan Iskandar,Sun, Jiulong,Chuah, Gaik-Khuan,Jaenicke, Stephan
, p. 719 - 726 (2015/03/18)
Polysubstituted furans were obtained with excellent yields via the electrophilic alkynylation of 1,3-dicarbonyl compoundsws with phenyl- or ester-substituted brominated alkynes. The reaction is catalyzed by the inexpensive and readily available catalyst, cobalt(II) chloride, and has a wide substrate scope. The C(sp)-C(sp3) coupling occurs under mild conditions with short reaction times and does not require an inert atmosphere or ligands. It is proposed that the reaction proceeds through a chelation complex of cobalt(II) with the deprotonated 1,3-dicarbonyl compound.
Direct oxidative coupling of enamides and 1,3-dicarbonyl compounds: A facile and versatile approach to dihydrofurans, furans, pyrroles, and dicarbonyl enamides
Li, Pan,Zhao, Jingjing,Xia, Chungu,Li, Fuwei
, p. 5992 - 5995 (2015/01/08)
An efficient manganese(III)-mediated oxidative coupling reaction between α-aryl enamides and 1,3-dicarbonyl compounds has been developed. A series of dihydrofurans and dicarbonyl enamides were synthesized in moderate to good yields. Moreover, these dihydrofurans could be readily transformed into the corresponding furans and pyrroles via the Paal-Knorr reaction.
Regioselective synthesis of highly functionalized furans through the RuII-catalyzed [3+2] cycloaddition of diazodicarbonyl compounds
Xia, Likai,Lee, Yong Rok
, p. 3430 - 3442 (2014/06/09)
A novel method for the RuII-catalyzed regioselective synthesis of highly functionalized furans from readily available cyclic and acyclic diazodicarbonyl compounds and terminal alkynes is described. The devised protocol offers a straightforward means to the construction of a variety of diverse furan derivatives through powerful cascade processes, including the formation of ruthenium carbenoid, cyclopropenation, ring-opening metathesis, and cyclization. Copyright
Pd(II)-catalyzed sequential C-C/C-O bond formations: A new strategy to construct trisubstituted furans
Zheng, Meifang,Huang, Liangbin,Wu, Wanqing,Jiang, Huanfeng
supporting information, p. 1838 - 1841 (2013/06/04)
Palladium-catalyzed oxidative difunctionalization of enol ethers with 1,3-dicarbonyl compounds to construct trisubstituted furans in one step under mild conditions is described. The reaction is thought to proceed through a C-C bond formation along with a C-O bond closing the ring structure. Oxygen is the sole oxidant regenerating the Pd(II) catalyst.
Silver-mediated oxidative C-H/C-H functionalization: A strategy to construct polysubstituted furans
He, Chuan,Guo, Sheng,Ke, Jie,Hao, Jing,Xu, Huan,Chen, Hongyi,Lei, Aiwen
supporting information; experimental part, p. 5766 - 5769 (2012/05/07)
A novel silver-mediated highly selective oxidative C-H/C-H functionalization of 1,3-dicarbonyl compounds with terminal alkynes for the creation of polysubstituted furans and pyrroles in one step has been demonstrated. Promoted by the crucial silver specie
One-pot synthesis of furans using base- and acid-supported reagents Na 2CO3/Al2O3-PPA/SiO2'
Aoyama, Tadashi,Nagaoka, Takashi,Takido, Toshio,Kodomari, Mitsuo
experimental part, p. 619 - 625 (2011/04/15)
A convenient method for the one-pot synthesis of furans from -keto esters and -halo ketones was developed using an acid- and base-supported reagent system Na2CO3/Al2O3-PPA/SiO2'. The condensation reaction of triketones, which are formed from the reaction of -keto esters with -halo ketones in the presence of Na2CO 3/Al2O3, was promoted by PPA/SiO2 to give the corresponding furans in good yields. This method is simple and easy to perform in comparison with stepwise processes, and the yields are good.
Microwave-assisted synthesis of 4-keto-4,5,6,7-tetrahydrobenzofurans
Goncalves, Sylvie,Wagner, Alain,Mioskowski, Charles,Baati, Rachid
scheme or table, p. 274 - 276 (2009/04/11)
The use of TMSCl in methanol under microwave irradiation allows the facile intramolecular condensation of a large panel of triketones, giving rise to 4-keto-4,5,6,7-tetrahydrobenzofurans in good to excellent yields.
Synthesis of polyfunctionalized furans from 3-acetyl-1-aryl-2-pentene-1,4-diones
Onitsuka, Satoaki,Nishino, Hiroshi
, p. 755 - 765 (2007/10/03)
The BF3-catalyzed cyclization of 3-acetyl-1-aryl-2-pentene-1,4-diones 1a-e in the presence of water in boiling tetrahydrofuran gave bis(3-acetyl-5-aryl-2-furyl)methanes 2a-e in 26-79% yields along with a small amount of 3-acetyl-5-aryl-2-methylfurans 3a-e. The exact structure of 2a was determined by X-ray crystallography. The use of a half volume of the solvent for the reaction of 1a resulted in the formation of 2,4-bis(3-acetyl-5-phenyl-2-furfuryl)-3-acetyl-5-phenylfuran (4) together with 2a and 3a. A similar reaction of 1a was carried out in the presence of 3-acetyl-5-(4-methylphenyl)-2-methylfuran (3d) to afford 4-(3-acetyl-5-phenyl-2-furfuryl)-3-acetyl-5-(4-methylphenyl)-2-methylfuran (5) in 49% yield. The BF3-catalyzed reaction of 1a with 2,4-pentanedione in dry tetrahydrofuran at 23°C gave 3-(3-acetyl-5-phenyl-2-furfuryl)-4-hydroxy-3-penten-2-one (6a) and 3-(3-acetyl-2-methyl-4-phenyl-5-furyl)-4-hydroxy-3-penten-2-one (7a) in 66 and 24% yields, respectively. The product distribution depended on the reaction temperature. A similar reaction of 1b-e also yielded the corresponding trisubstituted furans 6b-e and tetrasubstituted furans 7b-e in good yields. These results suggested the presence of the furfuryl carbocation intermediate A during the reaction. The one-pot synthesis of 6a and 7a was also achieved by a similar reaction using phenylglyoxal. The deoxygenation of 1a with triphenylphosphine gave 3a in 88% yield, while 1a was treated with concentrated hydrochloric acid to yield 3-acetyl-2-chloromethyl-5-phenylfuran (8) which was quantitatively transformed in ethanol into 3-acetyl-2-ethoxymethyl-5-phenylfuran (9) and in water into 3-acetyl-5-phenylfurfuryl alcohol (10), respectively. In addition, the Diels-Alder reaction of cyclopantadiene with 1a gave the corresponding [4+2] cycloaddition products 11 and 12.
