850147-87-4Relevant articles and documents
B(C6F5)3-catalyzed O-H insertion reactions of diazoalkanes with phosphinic acids
Jiang, Jun,Zhang, Xinzhi,Zhang, Yangyang,Zhao, Jincheng
, p. 5772 - 5776 (2021/07/12)
A highly efficient base-, metal-, and oxidant-free catalytic O-H insertion reaction of diazoalkanes and phosphinic acids in the presence of B(C6F5)3has been developed. This powerful methodology provides a green approach towards the synthesis of a broad spectrum of α-phosphoryloxy carbonyl compounds with good to excellent yields (up to 99% yield). The protocol features the advantages of operational simplicity, high atom economy, practicality, easy scalability and environmental friendliness.
Catalytic Enantioselective Protonation/Nucleophilic Addition of Diazoesters with Chiral Oxazaborolidinium Ion Activated Carboxylic Acids
Kang, Ki-Tae,Kim, Seung Tae,Hwang, Geum-Sook,Ryu, Do Hyun
supporting information, p. 3977 - 3981 (2017/03/27)
A new chiral Br?nsted acid derived from carboxylic acid and a chiral oxazaborolidinium ion (COBI), as an activator, is introduced. This acid was successfully applied as a catalyst for the highly enantioselective protonation/nucleophilic addition of diazoesters with carboxylic acids.
Highly enantioselective catalytic 1,3-dipolar cycloadditions of α-alkyl diazoacetates: Efficient synthesis of functionalized 2-pyrazolines
Lee, Sung Il,Kim, Ka Eun,Hwang, Geum-Sook,Ryu, Do Hyun
supporting information, p. 2745 - 2749 (2015/04/22)
Highly enantioselective 1,3-dipolar cycloaddition reactions of α-substituted diazoacetates are accomplished by catalysis of the chiral oxazaborolidinium ion. Functionalized 2-pyrazolines are synthesized in high to excellent enantiomeric ratios (up to >99:
Catalytic carbon insertion into the β-vinyl C-H bond of cyclic enones with alkyl diazoacetates
Lee, Sung Il,Kang, Byung Chul,Hwang, Geum-Sook,Ryu, Do Hyun
supporting information, p. 1428 - 1431 (2013/06/26)
The first example of the boron Lewis acid catalyzed Csp2-H functionalization of cyclic enones was achieved using diazoacetates. The insertion of the carbon atom of diazoacetates utilizes BF3? Et2O or a newly designed oxaza
Catalytic enantioselective carbon insertion into the β-vinyl C-H bond of cyclic enones
Lee, Sung Il,Hwang, Geum-Sook,Ryu, Do Hyun
supporting information, p. 7126 - 7129 (2013/07/05)
Chiral oxazaborolidinium ion-catalyzed Csp2-H functionalization of enones using diazoacetate has been developed. Various β-substituted cyclic enones were synthesized in high yield (up to 99%) with high to excellent enantioselectivity (up to 99%
CuO/SiO2 as a simple, effective and recoverable catalyst for alkylation of indole derivatives with diazo compounds
Fraile, Jose M.,Le Jeune, Karel,Mayoral, Jose A.,Ravasio, Nicoletta,Zaccheria, Federica
supporting information, p. 4327 - 4332 (2013/08/23)
The purely inorganic copper oxide on silica catalyzes the reaction of methyl phenyldiazoacetate with N-methyl indole under mild reaction conditions, giving the alkylation (formally a C-H insertion) in position 3, and the catalyst can be recovered and reused at least in 5 consecutive runs with only minor loss in activity. The scope of the reaction includes various diazo compounds and indole or pyrrole derivatives leading to alkylation or cyclopropanation depending on the heterocycle structure. An alternative mechanism, without reduction of Cu(ii) to Cu(i), is proposed on the basis of the obtained results. The Royal Society of Chemistry 2013.
Enantioselective synthesis of α-alkyl-β-ketoesters: Asymmetric Roskamp reaction catalyzed by an oxazaborolidinium ion
Gao, Lizhu,Kang, Byung Chul,Hwang, Geum-Sook,Ryu, Do Hyun
supporting information; experimental part, p. 8322 - 8325 (2012/09/08)
Breaking kamp: A catalytic route toward chiral α-alkyl-β- ketoesters using the title reaction of α-alkyl diazoester with aldehydes has been developed (see scheme). The reaction proceeds with high to excellent enantioselectivities and this methodology was applied to a concise two-step synthesis of the natural pheromone sitophilate. Copyright
Desymmetrizing asymmetric ring expansion of cyclohexanones with α-diazoacetates catalyzed by chiral aluminum Lewis acid
Hashimoto, Takuya,Naganawa, Yuki,Maruoka, Keiji
supporting information; experimental part, p. 8834 - 8837 (2011/08/03)
Chiral aluminum Lewis acid catalyst composed of Me3Al and 3,3′-bis(trimethylsilyl)-BINOL in a 2:1 ratio was found to promote novel catalytic asymmetric ring expansion of cyclohexanone with α-substituted α-diazoacetates to give seven-membered rings with an all-carbon quaternary center. Application of this strategy to 4-substituted cyclohexanones opened up a novel way for the catalytic desymmetrizing asymmetric construction of cycloheptanones bearing remote α,δ-chiral centers.
Catalytic asymmetric roskamp reaction of α-Alkyl-α-diazoesters with aromatic aldehydes: Highly enantioselective synthesis of α-Alkyl-β-keto esters
Li, Wei,Wang, Jun,Hu, Xiaolei,Shen, Ke,Wang, Wentao,Chu, Yangyang,Lin, Lili,Liu, Xiaohua,Feng, Xiaoming
supporting information; experimental part, p. 8532 - 8533 (2010/08/06)
The first catalytic enantioselective Roskamp reaction of α-alkyl-α-diazoesters with aromatic aldehydes was realized using a simple chiral N, N′-dioxide-scandium(III) complex. Remarkably, with 0.05 mol % catalyst, the reaction was performed well over a series of substrates, giving the desired products chemoselectively in excellent yields (up to 99%) and enantioselectivities (up to 98% ee) under mild conditions. This protocol provides a promising method for the synthesis of chiral α-alkyl-β- keto esters and 1,3-diols.
Stereoselective construction of seven-membered rings with an all-carbon quaternary center by direct tiffeneau-demjanov-type ring expansion
Hashimoto, Takuya,Naganawa, Yuki,Maruoka, Keiji
supporting information; experimental part, p. 6614 - 6617 (2009/09/26)
Insertion of one methylene unit into the C-C bond of cyclohexanones is apotentially useful, straightforward method for the construction of seve n-membered carbocycles. An especially appealing but largely unexplored method in this arena is the nucleophilic
