Grignard reaction Halogen compounds

InPhj mp 208°, TlPhj mp 170°. For Ga and In compounds the primary M-C bonds can be cleaved by HX, X2 or MX3 to give reactive halogen-bridged dimers (R2MX)2. This contrasts with the unreactive ionic compounds of T1 mentioned above, which can be prepared by suitable Grignard reactions ... 

Mg powder can probably be activated for any subsequent Grignard reaction by treating the metal with MesSiCl 14 in either ether or THF, or entirely without solvent, followed by removal of unreacted MesSiCl 14 and HMDSO 7 and any ether or THF in vacuo before adding the halogen compound dissolved in ether or THF (Scheme 13.14). 

Reaction XLIII. (c) Condensation of a-Halogen Fatty Acid Esters with Aldehydes and Ketones by means of Zinc or Magnesium (Reformatsky-Grignard). (C., (1901), I., 1196 II., 30 (1902), I., 856.)—This is an extension of the Grignard and zinc alkyl reactions which enables a-halogen esters to be condensed with carbonyl compounds as if they were simple alkyl halogen compounds. The zinc or magnesium alkyl derivative is neither prepared beforehand nor isolated in the reaction, but there is little doubt that some such compound is transitorily formed. Zinc is the metal... 

Coupling to produce dimeric product was a side reaction in these systems also, e.g. 75 % dimer formation was reported for poly(styryl)lithium and 23 % dimer formation with the poly(styryl)-Grignard reagent 326). However, it should be noted that the only reported characterizations of these reactions were size exclusion chromatography traces and silver catalyzed polymerization of tetrahydrofuran using the polymeric halogen compounds as co-initiator. 

Anilides, toluides, and a-naphthalides ate prepared from phenyl, p-tolyl, and a.-naphthyl isocyanates, respectively, by reaction with a Grignard reagent. The reaction is valuable for the identification of halogen compounds of the type that form organometallic derivatives. The reaction occurs in ether solution at room temperature. In general, the yields of N-arylamides are excellent. This method has been used in the preparation of N-(a.-furyl)-propionamide (89%). ... 

The hydroxy function may originate from the reduction of an a-halogenated carbonyl compound or a Grignard reaction. The oxirane oxygen is not always incorporated directly from a hydroxy group for instance, in the case of a carboxylic acid ester, it is derived with neighboring-group participation from an ortho-monoester intermediate. 

Some examples of the lower reactivity of acetylenic Grignard reagents are the 1,2-addition reactions involving benzonitrile [29], and nucleophilic substitution reactions with halogen compounds that are limited to those highly reactive compounds, such as... 

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