The Effect of Rapid Addition of Halide on the Yields of Some Grignard Reagents

Abstract

YIELDS OE GRIGNARD REAGENTS. II 1583 an excellent yield of benzylmagnesium chloride (see following paper);whereas if allyl bromide is added at once to magnesium in ether, very little allylmagnegium bromide results, and most of the allyl bromide couples to form diallyl. However, by the special conditions described recently by Gilman and McGlumphy12 it is possible to obtain allylmagnesium bromide in greater than 90% yields. The Naphthylmagnesium Bromides.-The yield of a-naphthylmagnesium bromide reported earlier215 is incorrect. This was very probably due to the sparing solubility of this Grignard reagent in ether (see footnote h to Table I). The comparatively high yield of /3-naphthylmagnesium bromide is both interesting and valuable in view of the discouragingly low yields of this RMgBr compound reported by others.13

The Action of Grignard Reagents on Heavy Metal Salts. Iii. Mixed Grignard Reagents and Silver Bromide

“…Halogen was determined volumetrically on the same sample. The hydroxyl-halide ratios so obtained indicated yields comparable to those reported by Gilman and his co-workers (7). In the case of feri.-butylmagnesium bromide, 2.5 moles of magnesium was used for each mole of tert.-butyl bromide.…”

Generalized syntheses of .gamma.-diketones. I. Addition of dimetalloacetylides to aldehydes. II. Dialkylation of bisdithianes

“…II. Dialkylation of Bisdithianesla Walter B. Sudweekslb and H. Smith Broadbent* Department of Chemistry, Brigham Young University, Provo, Utah 84602 Received April 23,1974 y diketones are synthetically very useful but not generally accessible. Extensive preliminary studies revealed that the addition of dimetalloacetylides to aldehydes followed by catalytic reduction of the carbon-carbon triple bond and then oxidation of the saturated glycol to the diketone was one of the more promising approaches.…”

“…The addition of acetylene was continued until hydrolysis of an aliquot of the supernatant liquid formed only a negligible amount of base as determined by titration. 23 In the case in which benzene solvent was used, the ethyl Grignard reagent was prepared in the usual manner, and the bulk of the ether was distilled off. An equal volume of dry benzene was then added, and the acetylene treatment was carried out as described above.…”

Etudes sur les composés organométalliques I action du chlorure de benzylmagnésium et du bromure de phénylmagnésium sur le tétrachlorure de titane

“…2. Les chlorure de benzylmagnlsium et bromure de phdnylmagndsium ont BtB pr6parCs de fayon habituelle [7]. Le magnesium est en excks de 10% par rapport & l'halogdnure organique.…”