A reaction with Grignard

Reactions of Oxiranes A. Reaction with Grignard Reagents... 

Ferrocene is easily prepared by the direct reaction process or by a reaction with Grignard reagents as shown in eqs. (15.2) and (15.5). Keal and Pauson [9] and Miller [8] found that ferrocene is stable in water, 10% NaOH aqueous solution, and concentrated hydrochloride acid at around the boiling point. It sublimates at 100 "C without decomposition and is stable up to 470 °C under a nitrogen atmosphere. It dissolves in organic solvents such as alcohol, ether and benzene. As a solid and a solution it is stable in air [8,9,25]. 

Whereas sulfolane is relatively stable to about 220°C, above that temperature it starts to break down, presumably to sulfur dioxide and a polymeric material. Sulfolane, also stable in the presence of various chemical substances as shown in Table 2 (2), is relatively inert except toward sulfur and aluminum chloride. Despite this relative chemical inertness, sulfolane does undergo certain reactions, for example, halogenations, ting cleavage by alkah metals, ring additions catalyzed by alkah metals, reaction with Grignard reagents, and formation of weak chemical complexes. 

The work on vinyl sulphones and their reactions with Grignard reagents, in the presence of transition metal catalysts, all emanates from Julia s laboratory191-195, with the exception of a note196 that presents evidence for SET processes in the alkylation of vinyl sulphones by organometallic reagents. 

When the carbonyl carbon is substituted with a potential leaving group, the tetrahedral adduct can break down to regenerate a C=0 bond and a second addition step can occur. Esters, for example are usually converted to tertiary alcohols, rather than ketones, in reactions with Grignard reagents. 

The mono-alkylated species N3P3C15R is a good synthon for the generation of geminally substituted products by further reaction with Grignard reagents (Eq. 4) (150)... 

House and Trafkante suggested that magnesium alkoxides promote deprotonation of ketones in the reaction with Grignard reagents leading to by-products. See Reference 18(a). 

Aromatic and vinylic sulfides take part in cross-coupling reactions with Grignard reagents in the presence of Ni catalysts.336,337 This reaction has been applied to the enantioselective synthesis of binaphthyls using a standard chiral oxazoline ligand (Equation (25)) 338... 

The simple addition and the conjugate addition reactions compete with each other. Figure 11-23 shows an example of a reaction with both the simple addition and the conjugate addition products. In this reaction, an increase in the size of the alkyl group on the Grignard reagent leads to an increase in the yield of the conjugate addition product, while substitution on the C=C leads to an increase in the yield of the simple addition product. 

The benzotriazole moiety of iV-(a-aminoalkyl)benzotriazoles is readily replaced by hydride upon reduction with sodium borohydride, or with a carbanion by reaction with Grignard or lithium reagents. These are two most important reactions of benzotriazole derivatives from which versatile routes have been developed for the synthesis of primary, secondary, and tertiary amines. 

Reaction with Grignard reagent, RMgX in ether yields dialkyl gold(lll) chloride, R2AUCI3, which may be converted readily to other dialkyl gold(lll) complexes by replacement of the chloride anion by a donor hgand. 

A new approach to this synthesis category involves the dimerization of halogenated oxime ethers 705 by reaction with Grignard reagents, where the C-2 atom of the product 706 arises from a rearrangement that is proposed to proceed via azirene intermediates <2002JA9032, 2004CL122>. 

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