The sodium derivatives of the nitrile-esters of 2-methylpropene-1,1,3,3-tetracarboxylic acid (HOOC)2C=C(CH3)–CH(COOH)2 have been synthesized, and their properties have been compared with those of the corresponding compounds of the propene-1,1,3,3-tetracarboxylic acid series synthesized previously. It has been observed that, with one exceptional case of the 1,3-dicyano-1,3-dicarbethoxy-compounds, there exist analogies in all respects between the 2-methylpropene-tetracarboxylic acid series and the propenetetracarboxylic acid series.
(1) The Raman spectra of the following substances have been measured: Sesquichamene. d-sabinene, d-α-pinene, d-verbenol, d,l-Δ1-terpinenol-(4), menthyl acetate, and isobornyl acetate. (2) The occurrence of the intense line at Δν 1682cm.−1 seems to suggest that sesquichamene may have a linkage of 1-methyl-cyclohexene-(1) if cedrene has a linkage of 1-methyl-cyclopentene-(1).
(1) Rotatory dispersions in the region from 6708 Å to 4358 Å of diethyl and dimethyl isopropylidene-tartrates, diethyl and dimethyl ethylidenetartrates and diethyl methylene-tartrate, bridged derivatives of alkyltartrates, in which both the hydroxyls are linked with the rest of the carbonyl compounds have been measured, all with no solvent, and shown to be expressed by one term of Drude’s equation. (2) It is pointed out that the absorption bands of the condensation products from ketone are located at about 1750 Å, whereas those of the compounds derived from aldehydes at about 2100 Å, and the relation between these values and the chemical constitution is discussed. (3) Considering the fact that the dispersion ratio α4358⁄α5461 and the characteristic wave length λ0 range from 1.674 to 1.748 and from 1735 Å to 2141 Å respectively, the rotatory dispersion of these compounds is concluded to be very probably simple.