Grignard compounds hydrolyzable

Wowk and Di Giovanni found that after a vinyl Grignard compound had been stored for some time, then hydrolyzed with dilute acid, the gases produced, in addition to the expected ethylene, also contained considerable amounts of ethane, hydrogen and several Ci and C5 alkanes and alkenes, making a gas-volumetric method unsuitable for assay purposes. 

Cuprous iodide catalyzes the reaction of various alkyl chlorides, bromides, and iodides in hexamethylphosphoric triamide (HMPT), to give the complexed product RaSnXj, which can then be further alkylated with a Grignard reagent, or can be hydrolyzed to the oxide and converted into various other compounds, R2SnY2 (43). This promises to be a useful laboratory method, e.g.,... 

Organometallic compounds can be hydrolyzed by acid treatment. For active metals such as Mg, Li, and so on, water is sufficiently acidic. The most important example of this reaction is hydrolysis of Grignard reagents, but M may be many other metals or metalloids. Examples are SiRs, HgR, Na, and B(OH)2- Since aryl Grignard and aryllithium compounds are fairly easy to prepare, they are often used to prepare salts of weak acids, for example,... 

At present (2007), lOOC is carrying out some ring tests in order to verify the accordance of the two methods of elution. Separation on the basis of unsaturation can be improved by modifying the stationary phase by Ag-F ions, as the dimension of Ag+ ion is suitable to interfere with n bonds. Christie [10-12] adopted this technique to carry out structural analysis of TAGs. TAGs were hydrolyzed by Grignard reaction, then the stereoisomers 1,2 and 1,3-diacylglyreols were transformed into diasteroisomers by derivatization with a chiral compound, and were separated on normal-phase (NP)-HPLC. 

The cyanohydrin not only adds an additional C at the site of the C==0 but also introduces two new functional groups, OH and CN. which can be used to introduce other functional groups. The OH can be used to form an alkene (C=C), an ether (—RO), or a halogen compound (C—X) the C N can be reduced to an amine (CHjNHj), be hydrolyzed to a carboxyl (COOH) group, or react with Grignard reagents if the OH is protected. 

In Methods 3a to 3d. enolization of carbonyl compound and reduction of RMgX are side reactions that become important for hindered ketones and bulky Grignard reagents (Section 14-12A). Ammonium chloride is used to hydrolyze the reaction mixtures in preparation of tertiary alcohols to avoid dehydration. Organolithium compounds are superior to RMgX for preparation of bulky tertiary alcohols. 

The entire area of organosilicon chemistry blossomed with Kipping s preparation of such compounds by the more convenient Grignard process. These silanes turned out to be of paramount importance since they hydrolyzed readily to form compounds containing Si-0 bonds, both linear and cyclic.12,22,24 28 These new materials were first called silicoketones or silicones by analogy with ketones in the organic area. Structural studies, however, showed that they did not contain the Si=0 double bond. Thus, the silicone name is a misnomer, but it has persisted, at least in casual usage. However, the terms siloxanes and polysiloxanes are preferred. 

Dialkynyl ketones.1 In the presence of Cl Pd[P(C6H5),]2 1 couples with al-kynyltin compounds (2) to give (N-phenyl)dialkynylimines (3) in 30-75% yield. These products are hydrolyzed to dialkynyl ketones (4) by aqueous acetone (BF, etherate) in —60% yield. Under the same conditions, Grignard reagents undergo coupling to alkanes. 

The 5(2H)-oxazolones (213) present two sites, C(4) and C(5), to nucleophilic attack they usually react at the latter. The benzylidene derivative (214), the most thoroughly studied member of this class, possesses an additional electrophilic centre at the exocyclic carbon atom. However, alkaline hydrolysis of this compound affords phenylacetamide and benzoylformic acid by acyl-oxygen fission (equation 50). a-Keto acids are also obtained when 2-trifluoromethyl-5(4//)-oxazolones are hydrolyzed, the reaction involving preliminary isomerization to a 5(2//)-oxazolone. The example shown in equation (51) represents the first non-enzymatic synthesis of an optically active a-keto acid. An instance of nucleophilic attack at C(4) of a 5(2//)-oxazolone is the formation of the oxazolidinone (215) in a Grignard reaction (equation 52). However, the typical behaviour of unsaturated pseudooxazolones like (214) is conjugate addition of a nucleophile, followed by further transformations of the resulting 5(4F/)-oxazoIones. This is illustrated by the reaction of compound (214) with benzene in the presence of aluminum chloride to yield, after aqueous work-up, the acylamino acid (216 equation 53). 

Arenetellurolates are obtained when tellurium is reacted with aromatic lithium compounds in THF or diethyl ether (p. 154) or with aromatic Grignard reagents in THF. The arenetellurolates thus formed are hydrolyzed to tellurols. The tellurols are oxidized to the diaryl ditellurium products. 

Amination. The azide reacts with aryl Grignard reagents at room temperature to form an intermediate, probably a triazene, that is hydrolyzed to an aniline in 70-90% yield. Aryllithium compounds can also be used, but yields are generally lower. 

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