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Gerrard, La##ert, and Silver. 1647* The composition (i.e., relative percentages of Iand 3-methylallyl compounds) of the product is shown in Table 2 and similarly for subsequent reactions involving 1-and 3-methylallyl derivatives.

The compounds (RCO2)6Zn4O have not been widely reported in the literature, and in order to examine their little-known chemistry, a number of them have been synthesised by several methods. The simplest method of preparation, using the carboxylic acid and zinc oxide, was found to be restricted to branched chain acids. The reaction of these basic salts with primary and secondary amines led to a breakdown of their structures, with the formation of the amine complexes of the neutral carboxylates.

Interaction of unsaturated alcohols (allyl, methallyl) (1, 2, and 3 mols., severally) with boron trichloride ( 1 mol.) gave the appropriate dichloroboronites, chloroboronates, and trialkenyl orthoborates. The alkenyloxyboron chlorides, which were also obtained from the borates and boron trichloride, were unstable, decomposing to the appropriate chloroalkene, but stable 1 : 1 and 1 : 2 complexes were obtained with pyridine. Neither these borates nor tripropynyl borate was attacked by hydrogen chloride a t 20°, but at 120' triallyl borate was dealkylated. Dealkylation by both hydrogen bromide and hydrogen iodide was accompanied by addition. Diallyl and dimethallyl ethers were easily cleaved by boron trichloride ; the mixed allyl methallyl ether reacted by methallyl-oxygen fission. Neither ammonia nor pyridine co-ordinated with triallyl borate, and the reaction with bromine was slow.STUDIES 1 on boron trichloride-alcohol and -ether systems have been extended to unsaturated compounds. The reactions of allyl and methallyl alcohols and their mixed and simple ethers and of propynol show a broad similarity to those of corresponding saturated systems, except that certain reactions are accompanied by addition. The allyl and the methallyl group appear to have reactivities intermediate between those of sec.-and tert.-alkyl groups.Triallyl borate,2 obtained in poor yield, is the only borate previously prepared by the interaction of boron trichloride and an unsaturated alcohol , although the preparation of triallyl3 and trimethallyl * borate from other starting materials has been described.Allyl, methallyl, and propynyl orthoborate have now been prepared in good yield by addition of boron trichloride (1 mol.) to the appropriate alcohol (3 mols.) in n-pentane at -80"; the reverse order of addition was less successful. By alteration of the relative proportions of the reagents evidence of the formation of intermediate alkenyloxyboron chlorides was obtained : BCI, + RO.BCI, -> (RO),BCI ,-+ B(OR),Of the alkenyloxyboron chlorides, the dichloroboronites, RO-BCl,, could not be adequately characterised owing to their instability, but stable 1 : 2 complexes with pyridine, and in the allyl system also a 1 : 1 complex, were obtained. The chloroboronates, (RO),BCl, whilst still unstable, were not as easily decomposed as the dichloroboronites ; a 1 : 2 complex with pyridine was obtained from diallyl chloroboronate, whilst the dimethallyl compound afforded a 1 : 1 complex. The alkenyloxyboron chlorides were also obtained from the appropriate orthoborate and boron trichloride ; their decomposition followed the general scheme observed earlier in saturated systems : l b 9 5 9 6General resemblance to saturated systems has been noted. BCl, BCl, B(OR), + (RO),B*CI + RO-BC1, 3RO*BC12 __t 3RC1 + B203 + BCI, 3(RO),BC1< 3RC1 + B,O, + B(OR),Pyrolysis of the 1 : 1 complex between allyl dichloroboronite and pyridine was similar to that observed with the n-butyl analogue,' whilst the 1 : 1 complex between dimethallyl

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