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Triflimide

Scandium triflimidate, Sc[N(S02CF3)2]3, is also a very active acylation catalyst. [Pg.246]

Reversible O-silylation also enhances the electrophilicity of carbonyl dienophiles. For example, 10 mol % A-trimethylsilyl triflimide catalyzes the reaction of pent-3-en-2-one with cyclopentadiene. A hindered base, such as 2,6-/p/.S - -butyl-4-mclhylpyridinc improves the yield in cases in which the catalyst causes the occurrence of reactant degradation. [Pg.486]

The oxazaborolidines B and C derived from proline are also effective catalysts. The protonated forms of these catalysts, generated using triflic acid or triflimide, are very active catalysts,95 and the triflimide version is more stable above 0° C. Another protonated catalyst D is derived from 2-cyclopentenylacetic acid. [Pg.505]

Cationic oxazaborolidines derived from a,a-diphenylpyrrolidine-2-methanol have been examined and shown to considerably extend the range of dienophiles that are responsive to the catalysts." The best proton source for activation of these catalysts is triflimide, (CF3S02)2NH.100 For example, cyclohexenone and cyclopentadiene react with 93% enantioselectivity using catalyst J. [Pg.508]

In another procedure, (CH3)3SiN(03SCF3) is generated in situ from triflimide.91... [Pg.816]

The conditions using 2,4,6-collidine/Tf20 and having the reaction warm from -78 °C to 25 °C were chosen mainly to avoid using more expensive reagents such as 2,6-di-r-butyl-4-methylpyridine or A-phenyl triflimide. (a) Stang, P. J. Hanack, M. C. Subramanian, L. R. Synthesis 1982, 85. (b) McMurray, J. E. Scott, W. J. Tetrahedron Lett. 1983,24,979. [Pg.78]

PYRIDINE-DERIVED TRIFLATING REAGENTS N-(2-PYRIDYL)-TRIFLIMIDE AND N-(5-CHLORO-2-PYRIDYL)TRIFLIMIDE (Methanesulfonamide, l,l,l-trifluoro-N-2-pyridinyl-N-((trifluoromethyl)sulfonyl]-] and Methanesulfonamide, N-(5-chloro-2-pyrldinyl)-1,1,1-trifluoro-N-I(trffluoromethyl)sulfonyl]-)... [Pg.77]

A. N-(2-Pyridyl)triflimide (1). A 2-L, two-necked, round-bottomed Mask quipped with a mechanical stirrer (Note 1) and a rubber septum is charged with 2-aminopyridine (19.859 g, 0.211 mol) (Note 2) and pyridine (35.04 g, 35.88 ml, 0.443 mol) (Note 3) in 800 mL of dichloromethane (CH2CI2) (Note 4) under an argon... [Pg.77]

The spectral properties of N-(5-chloro-2-pyridyl)triflimide are as follows IR... [Pg.79]

PYRIDINE-DERIVED TRIFLATING REAGENTS N-(2-PYRIDYL)TRIFLIMIDE AND N-(5-CHLORO-2-PYRIDYL)-TRIFLIMIDE... [Pg.300]

Pyridine-Derived Triflating Reagents N-(2-Pyridyl)triflimide and N-(5-Chloro-2-pyridy l)triflimide. [Pg.281]

The reaction was catalyzed by Br203 in bmim NTf2, l-butyl-3-methyhmidazolium triflimide Gmouth,... [Pg.720]

Bhatt A I, May I, Volkovich V A, et al. Group 15 quaternary alkyl bis-triflimides Ionic liquids with potential application in electropositive metal deposition and as supporting electrolytes. J. Chem. Soc., Dalton Trans. 2002. 4532-4534. [Pg.476]

A unique class of steroidal alkaloids, the batrachotoxinins, is isolated in small quantities from the skins of poison arrow frogs and also from the feather of a New Guinea bird. One of the key steps during the total synthesis of (+)-batrachotoxinin A by Y. Kishi et al. was a Michael addition to form a seven-membered oxazapane ring. The removal of the primary TBS protecting group was achieved by treatment with TASF and the resulting alkoxide attacked the enone at the 3-position to afford an enolate as the Michael adduct. The enolate was trapped with phenyl triflimide as the end triflate. [Pg.287]

Alkylations Allyl and benzyl acetates serve as adequate alkylating agents to nucleophiles such as silyl ketene acetals when magnesium triflimide is used to activate them. In most cases this reagent is superior to magnesium perchlorate. [Pg.233]

Hetero-Diels-Alder reactions. The catalytic activity of MCjSiNTfj (generated from allyltrimethylsilane and triflimide) can be gauged by the condensation of methyl... [Pg.403]

Davis recently reported triflimide salts derived from classical Girard s reagents which are hydrazine derived onium salts [29],... [Pg.91]

Abstract Room temperature ionic liquids (ILs) have attracted considerable attention as novel reaction media over the last decade. By virtue of their unique properties, ILs have been proposed as alternative solvents. Structurally, most of the ILs that have been investigated to date are based on imidazolium, pyridinium and ammonium cations, associated with polyatomic anions such as chloroaluminates, tetrafluoroborate, hexafluorophoshate and bis-triflimide. Although these salts have positive properties, imidazole, pyridine and halogenoalkanes come from petroleum feedstocks that are neither green nor sustainable. Renewable resources may represent a valid alternative to synthesized new ILs an alternative able to take into accounts both the ecological and economic requirements. [Pg.14]


See other pages where Triflimide is mentioned: [Pg.932]    [Pg.144]    [Pg.125]    [Pg.268]    [Pg.269]    [Pg.54]    [Pg.354]    [Pg.183]    [Pg.133]    [Pg.8]    [Pg.351]    [Pg.318]    [Pg.61]    [Pg.78]    [Pg.78]    [Pg.79]    [Pg.283]    [Pg.116]    [Pg.827]    [Pg.687]    [Pg.1238]    [Pg.1013]    [Pg.232]    [Pg.233]    [Pg.26]   


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Catalysts triflimide

Gold triflimide

Gold-triflimide complexes

Phenyl triflimide

Triflimidates

Triflimidates

Triflimide salts

Triflimides

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