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Group 1 alkali metal organometallics

Organic compounds such as terminal alkynes (RC=CH) which contain relatively acidic hydrogen atoms form salts with the alkali metals, e.g. reactions 18.1, 18.2 and 13.30. [Pg.504]

A pyrophoric material is one that burns spontaneously when exposed to air. [Pg.504]

Colourless alkyl derivatives of Na and K are obtained by transmetallation reactions starting from mercury dialkyls (equation 18.4). [Pg.504]

Organolithium compounds are of particular importance among the group 1 organometallics. They may be synthesized by treating an organic halide, RX, with Li (equation 18.5) or by metallation reactions (equation 18.6) using n-butyllithium which is commercially available as solutions in hydrocarbon (e.g. hexane) solvents. [Pg.504]

YA Fig. 18.1 Part of a chain that makes up the polymeric structure of [Na(dme)][Cp] (dme= 1,2-dimethoxyethane) the zig-zag chain is emphasized by the hashed, red line. The structure was determined by X-ray diffraction [M.L. Coles et al. (2002) J. Chem. Soc., Dalton Trans., p. 896]. Hydrogen atoms have been omitted for clarity colour code Na, purple O, red C, grey. [Pg.504]

Similarly, in reaction 23.3, the acidic CH2 group in cyclopentadiene can be deprotonated to prepare the cyclopen-tadienyl ligand which is synthetically important in organometallic chemistry (see also Chapter 24). Na[Cp] can also be made by direct reactimi of Na with CsHg. Na[Cp] is pyrophoric in air, but its air-sensitivity can be lessened by complexing the Na+ ion with 1,2-dimethoxyethane (dme). In the solid state, [Na(dme)][Cp] is polymeric (Fig. 23.1). [Pg.848]

Dalton Trans., p. 896]. Hydrogen atoms have been omitted for clarity colour code Na, purple O, red C, grey. [Pg.849]


The chemical reactivities of the alkali metal organometallic compounds (RM) vary widely depending on metal M, basicity of the solvent systems used, and steric and electronic properties of the organic group R. In many reactions an important factor is the stabilization resulting from formation of a delocalized carbanion system as in the polymerization of dienes or aromatic substituted ethylenes, and in Reactions 3, 4, 5, and 10 in Table I. It is primarily with these delocalized carbanion systems that this review is concerned although saturated organolithium compounds are discussed briefly. [Pg.64]

Element halides are alkylated by alkali metal organometallic derivatives. Depending on the stoichiometry, one, several or all the halides are substituted by alkyl groups. The number of introduced alkyl groups is sometimes larger than the number of halides on the element, which yields ate (i.e. anionic) complexes. With transition-metal halides, the reaction sometimes goes along with some reduction of the oxidation state of the transition metal. [Pg.293]

Electronic Effects in Metallocenes and Certain Related Systems, 10, 79 Electronic Structure of Alkali Metal Adducts of Aromatic Hydrocarbons, 2, 115 Fast Exchange Reactions of Group I, II, and III Organometallic Compounds, 8,167 Fluorocarbon Derivatives of Metals, 1, 143 Heterocyclic Organoboranes, 2, 257... [Pg.509]

The slow development of heavy alkali organometallic chemistry is due to high reactivity, as rationalized by the increase of polar character of the metal-ligand bond due to the reduced polarizing ability of the metals. The increase in ionic character on descending the group of alkali metals is clearly demonstrated by the increase in ionic radii with Li+(0.69A), Na+(0.97A), K+(1.33A), Rb+(1.47A), and Cs+(1.67A), resulting in a radius of Cs+ that is more than double of that of Li+. [Pg.3]

A further complication in the reduction of aryl Group IV derivatives is the formation of biphenyl radical anion (135, 100, 97, 20) or its derivatives (32). However, this reaction is not peculiar to organometallic radical anions but appears to be quite general for alkali metal reduction of phenylated compounds (135). [Pg.286]

Starch can be vinylated with acetylene in the presence of potassium hydroxide in an aqueous tetrahydrofuran medium.1 1 The mechanism possibly involves the addition of the potassio derivative of starch across the carbon-carbon triple bond of acetylene, with subsequent hydrolysis of the organometallic intermediate to give the vinyl ether. Such a mechanism has been postulated for the formation of vinyl ethers from monohydric alcohols and acetylene, in the presence of an alkali metal base as catalyst.1 2 The vinylation of amylose is very similar to the vinylation of amylopectin, except for the relative ratio of mono- to di-substitution. With amylopectin, the proportion of disubstitution is greater. In both starches, the hydroxyl group on C-2 is slightly more reactive than the hydroxyl group on C-6 there is little substitution at the hydroxyl group on C-3. [Pg.269]


See other pages where Group 1 alkali metal organometallics is mentioned: [Pg.504]    [Pg.505]    [Pg.575]    [Pg.575]    [Pg.577]    [Pg.848]    [Pg.849]    [Pg.851]    [Pg.329]    [Pg.77]    [Pg.318]    [Pg.3218]    [Pg.137]    [Pg.504]    [Pg.505]    [Pg.76]    [Pg.317]    [Pg.3217]    [Pg.27]    [Pg.575]    [Pg.575]    [Pg.577]    [Pg.309]    [Pg.848]    [Pg.849]    [Pg.851]    [Pg.383]    [Pg.53]    [Pg.99]    [Pg.102]    [Pg.114]    [Pg.80]    [Pg.94]    [Pg.231]    [Pg.95]    [Pg.35]    [Pg.94]    [Pg.304]    [Pg.105]    [Pg.94]    [Pg.12]    [Pg.42]    [Pg.268]    [Pg.289]    [Pg.337]    [Pg.1493]    [Pg.93]   


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Alkali group

Organometallic group

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