An improved procedure to prepare 3-methyl-4-nitroalkylenethylisoxazoles and their reaction under catalytic enantioselective Michael addition with nitromethane.
نویسندگان
چکیده
Herein, we describe a short synthesis of 3-methyl-4-nitro-5-alkylethenyl isoxazoles and their reactivity as Michael acceptors. The title compounds reacted with nitromethane under phase-transfer catalysis to provide highly enantioenriched adducts (up to 93% ee) which were then converted to the corresponding γ-nitroacids.
منابع مشابه
On the role of DNA in DNA-based catalytic enantioselective conjugate addition reactions.
A kinetic study of DNA-based catalytic enantioselective Friedel-Crafts alkylation and Michael addition reactions showed that DNA affects the rate of these reactions significantly. Whereas in the presence of DNA, a large acceleration was found for the Friedel-Crafts alkylation and a modest acceleration in the Michael addition of dimethyl malonate, a deceleration was observed when using nitrometh...
متن کاملEnantioselective catalysis of the Henry reaction by a chiral macrocyclic ytterbium complex in aqueous media.
A chiral macrocyclic ytterbium cationic complex catalyses the nitro-aldol reaction between alpha-ketocarboxylates and nitromethane under ambient aqueous conditions, leading to the formation of for example, methyl-2-hydroxy-2-methyl-3-nitropropanoate in 96% yield and 59% enantiomeric purity. Monitoring of the paramagnetically shifted intermediate Yb species by (1)H NMR allows several different s...
متن کاملAn Efficient and One-pot Procedure for the Synthesis of Chiral Isoxazolidine via Catalytic Highly Enantioselective 1,3-dipolar cycloaddition
Synthesis of enantiomerically pure isoxazolidine via an asymmetric 1,3- dipolar cycloaddition reaction of nitrone with electron-deficient dipolarophile was described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendate bis(imine)–Cu(II)triflate complex as catalyst. The reaction mechanism is discussed on the basis of the assignment of t...
متن کاملMultifunctional asymmetric catalysis.
Two types of general and practical enantioselective catalysts, namely, bimetallic complexes and Lewis acid-Lewis base bifunctional catalysts were developed based on the concept of multifunctional catalysis. In the first part of this review, the first example of a catalytic enatioselective nitro-Mannich reaction as well as a direct catalytic enantioselective aldol reaction of 2-hydroxyacetopheno...
متن کاملThree-Component Procedure for the Synthesis Chiral Spirooxindolopyrrolizidines via Catalytic Highly Enantioselective 1,3-Dipolar Cycloaddition of Azomethineylides and 3-(2-Alkenoyl)-1,3-Oxazolidin-2-ones
The catalytic highly regio-, diastereo-, and enantioselective synthesis of a small library of spiropyrrolizidineoxindolesvia a four-component 1,3-dipolar cycloaddition reactionof azomethineylides, derived from isatin, with electron-deficient dipolarophilewas described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendatebis(imi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 13 7 شماره
صفحات -
تاریخ انتشار 2015