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Halogen-metal interconversions with halogenated

Halogen-Metal Interconversions with Halo-geneted Anilines. A highly explosive compound which appears to be p-N,N-Trilithioani-line is formed as a by-product in the reaction of BuLi and p-Br-aniline but not o-Br-aniline (Ref 1). More recently this reaction was repeated but no by-product is mentioned (Ref... [Pg.9]

Many organic halides do not react satisfactorily with lithium to form RLi ecMnpounds or with metallic magnesium to form Grignard reagents. The desired organolithium compound can often be prepared by a halogen-metal interconversion reaction ... [Pg.929]

Thiophenedithiol (170) has been prepared by halogen-metal interconversion between the lithium salt of 4-bromo-3-thiophenethiol and n-butyllithium at —70°C, followed by reaction with sulfur/ IR, NMR, and UV spectra showed that this compound exists in the dithiol form (170). The compound obtained as a by-product in the... [Pg.87]

Halogen-metal interconversion between bromothiophenes and n -butyllithium occurs almost instantaneously and in very high yield. The reaction with 3-bromothiophene is usually carried out at -70 °C to avoid any (rans-lithiation. When bromine-lithium exchange takes place, steric crowding in the molecule decreases. As a consequence the percentage of 2-lithio derivative in relation to the 5-lithio isomer formed from 3-alkyl-2,5-... [Pg.830]

R. G. Jones, H. Gilman, The Halogen-Metal Interconversion Reaction with Organolithium Compounds, ... [Pg.255]

The halogen-metal interconversion reaction with organolithium compounds... [Pg.579]

The Halogen-Metal Interconversion Reaction with Organolithium Compounds ... [Pg.418]

By halogen-metal interconversion, Murray et al. prepared nicotinic acid labeled with i C (82% yield) or (62% yield) on the carboxyhc radical. Using M-butyl lithium and 3-bromopyridine, 3-pyridyl hthium was prepared and carbonation of this compound was carried out with i C02 or COa generated from the respective labeled barium carbonates with acid. [Pg.48]

The Gihnan-Swiss test, or Color Test II [151], is specific to alkyllithium reagents. Here, a halogen-metal interconversion in presence of an alkyllithium compound occurs with 4-bromo-iV,iV-dimethylaniline 70. After addition of benzophenone and, a few minutes later, concentrated hydrochloric acid, a bright red color for the triaryhnethyl cation 71 appears (Scheme 26.20). [Pg.763]

The halogen-metal interconversion, using organolithium compounds , also presents a problem of classification. One representation of its progress , shown below, makes it in one sense an electrophilic substitution, and with a clear recognition of the ambiguity, we shall for classification purposes regard it as such. [Pg.170]


See other pages where Halogen-metal interconversions with halogenated is mentioned: [Pg.76]    [Pg.11]    [Pg.3]    [Pg.42]    [Pg.76]    [Pg.82]    [Pg.442]    [Pg.214]    [Pg.4]    [Pg.27]    [Pg.44]    [Pg.138]    [Pg.42]    [Pg.39]    [Pg.50]    [Pg.416]    [Pg.813]    [Pg.822]    [Pg.822]    [Pg.830]    [Pg.27]    [Pg.44]    [Pg.250]    [Pg.94]    [Pg.97]   


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Halogen/metal interconversion

Halogens with metals

Metal-halogen

With Halogens

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