The Propargylic Rearrangement. IV. The Carbonation Products of Propargylmagnesium Bromide

Abstract

precipitate is obtained. The analyses3 support the formula for bistrichlorostibine-triscarbonmonoxide iron, Fe( CO)r-(SbC13)*: Fe, 10.4 (calcd. 9.37); Sb, 39.3 (calcd. 40.83); C1, 34.4 (calcd. 35.70). The presence of carbon monoxide was shown qualitatively and a rough qualitative estimate of the gas evolved on thermal decomposition of the compound agrees with the other analyses. Like iron pentacarbonyl, the antimony trichloride complex is photosensitive, darkening on exposure to light, and consequently the reactions were carried out in absence of light.Both the nickel and iron complexes are amorphous powders, insoluble in organic solvents such as benzene, pentane, cyclohexane and carbon tetrachloride. Carbon disulfide reacts, liberating carbon monoxide and leaving dark colored residues. With alcohols and acetone, decomposition occurs, carbon monoxide is evolved, and solutions of divalent nickel and iron result, leaving a precipitate of antimony oxychloride. With water, dilute acids and alkalies, similar rapid reactions occur with loss of carbon monoxide, giving nickelous or ferrous solutions or hydroxides, antimony oxychloride or antimonate. The compounds are decomposed on heating to give carbon monoxide and, in the case of the iron compound, some metal carbonyl together with antimony trichloride. On treating the compounds with phosphorus trichloride, there is a vigorous reaction evolving carbon monoxide and it is possible that further substitution occurs; the color of the residue is darker but no analyses have been made.The great difference in properties between the antimony trichloride substitution compounds of nickel and those formed by the phosphorus halides may be due to the increasing inertness of the electron pair in the antimony halides compared with the phosphorus halides. Presumably there is also a lowered tendency to form T bonds with nickel which operate t o stabilize metal complexes. Efforts to identify further antimony trichloride substitution products were without success.Thanks are due to Mr. Thomas Vasilos for his assistance in part of the work, and to Professors John Kr. Irvine, Jr., and Charles D. Coryell for their valuable advice and discussions.

Synthesis of 4-(1-Naphthyl)-2-Butynoic Acid

“…According to Wotiz, et al (31), the monoacetylenic type of link should give a strong peak at 3.06 microns, as shown in Curve 1, for 3-(l-naphthyl)-l-propyne, and a strong peak at 4.4-4.57 µ for the disubstituted acetylenic compounds, as shown in Curves 3 and 4. Aliene formation of the propyne was demonstrated by a peak at 5.16 microns in Curve 1, as had previously been pointed out by Wotiz, et al (32) in his work with acetylenic and allenic aliphatic acids, which substantiated the active hydrogen determinations reported in our paper.…”

“…The infrared curve of 4-(l-naphthyl)-2-butynoic acid (Curve 3) was compared with that of 3-(1-naphthyl) -2-propynoic acid (Curve 4) to establish the presence of an acetylenic bond. Both of these compounds showed an absorption peak at 4.5 microns, which is in agreement with the work of Wotiz, et al (32) on aliphatic acetylenic acids. The carboxyl groups were also clearly shown and there was some evidence of dimer formation, as indicated by a small peak at 5.7 microns.…”

The Chemistry of Allenes

“…The first to report such reactions was Marvel (196,542), who treated abromoacetylenes with sodium amalgam or magnesium and obtained alienes and allenic acids when the resulting solutions were hydrolyzed or carbonated (Eq 13). Subsequent work on reactions of this type has Na-Hg, ether; H,0® /-" /-BuC==CCBr Ph-i-Bu \ Mg,, ether; C02, H ¡Oá £-BuCH= C= CPh-i-Bu (Eq 13) i-BuO=C=CPh-t-Bu co2h led to a general method for the synthesis of allenecarboxylic acids, which consists of the treatment of propargyl bromides with magnesium, followed by carbonation of the resulting Grignard solution (205,462,605,606,608,609) (Eq 14). Unfortunately the allenic For some time it was assumed that the organometallic intermediate in such reactions is an acetylenic Grignard reagent, but extensive study has shown that in many cases, if not in all, it contains the allenic bond system (194,245,270,376,418,463).…”

Propargylmagnesium Bromide

“…Propargylmagnesium bromide adds to ketones, 9 aldehydes, 10 esters, 11 and Carbon Dioxide 12 to give a mixture of propargylic and allenic adducts. Additions to ketones and aldehydes (which can be present in the reaction mixture as the Grignard reagent is produced) 3,4 lead to mixtures of homopropargylic and allenic alcohols.…”

“…11b,c Carboxylation of propargylmagnesium bromide with CO 2 is also a low yield reaction that gives a mixture of acetylenic and allenic carboxylic acids. 12 The yield of carboxylic acids is better with the higher homologs of the propargyl Grignard reagent. Propargylation by Addition to C=N Bonds.…”