mal conductivity or heat of combustion and applied to correct the observed areas.The relative retention times of materials analyzed are as follows: low-boiling compounds (analyzed on 12 ft X 0.25 in.Abstract: Lithium dialkylor diarylcuprates (R2CuLi) react with aryl iodides in ether solution by competing metal-halogen exchange and coupling reactions. Using appropriate reagents, high yields of the coupled product R-Ar can be obtained by allowing the metal-halogen exchange to proceed to completion in the presence of an excess of RCuLi, and oxidizing the resulting mixture of organometallic species present in solution with nitrobenzene or oxygen. This reaction sequence works well with lithium di-n-alkyl-and diarykuprdtes; it fails with disec-alkyl-and di-t-alkylcuprates. Although most alkyllithium reagents react with aryl iodides only by metalhalogen exchange, methyllithium, uncomplexed with copper, smoothly converts aryl iodides to arylmethanes. Coupling of lithium dialkyl-and diarylcuprates with a/kyI halides appears to take place without significant metalhalogen exchange. The reaction of lithium diphenylcuprate with (-)-(R)-2-bromobutane occurs with the predominant inrersion of configuration (84-92% stereoselectivity) expected of an S~Z-like displacement. Coupling reactions involving an n-alkyl halide as one reaction partner proceed in high yield; those involving r-alkyl halides fail. Lithium di-n-alkyl-, di-sec-alkyl-, and di-t-alkylcopper reagents all couple with n-alkyl halides. A number of preparations for representative copper(1) ate complexes are described, and the sensitivity of the coupling reactions to the method of preparation of the ate complex, to the nature of the solvent, and to the presence of lithium halides, trialkylphosphines, and dialkyl sulfides in solution are discussed.(8) Normant has reported that use of hexamethylphosphoramide as solvent for the reaction of alkyl halides with Grignard reagents leads to synthetically useful yields of coupled products; however, the generality of this solvent effect has not yet been demonstrated: cf.

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The -chloro ketones, 2-chlorocyclohexanone (5), chloromethyl cyclohexyl ketone (7), and phenacyl chloride (13), have been converted to the corresponding enol acetates and trimethylsilyl enol ethers. These enol derivatives have served as precursors for the corresponding lithium -chloro enolates 6, 8, and 16 which are stable intermediates. Even the addition of copper(I) compounds or the formation of -mercuri derivatives of these enolates does not promote their decomposition to -ketocarbenes. In contrast, the -diazo derivatives 17 and 21 of acetophenone and methyl cyclohexyl ketone are readily decomposed by added copper(I) derivatives. The soluble complex, (n-BmS hCul, is an especially convenient catalyst for the decomposition of these -diazo ketones, compound 21 being rapidly decomposed in solution at 5-10°. With small amounts of this catalyst and excess olefin the norcarane derivative 22 was the major product. With an equimolar amount of this catalyst, the keto sulfide 26 (believed to arise from a sulfur ylide intermediate) became the major monomeric product.

Methacrylsäurechlorid (I) bildet bei längerem Lagem die cyclischen Dimeren (II), (III) und (IV), die in Form der Amide (V), (VI) und (VII) isoliert werden.