Kinetics of Catalytic Hydrogenation of Naphthyl-1-cyclopentenes and Naphthyl-1-cyclohexenes¹

Abstract

51 81 term [ K1lKe/[ H + ] + Klz] [ GI may be considered small and neglected. Since three values of K11 are available from part E, three equations may be formed in three unknowns; [k,!. Kl,K.], [knKln], and K.. Solving these equations it IS found that K. = 0.09, ktzKlt = 0.3285 and the term k1lKl1. K. is very nearly zero (ca. 0.0001). Therefore either kll or K11 is negligible. The fact that the rate is independent of [ H + ] at higher glycol concentration indicates that Kll is negligible and no appreciable Ce(OH)XaG is formed. Since very little Ce(0H)XsG is formed, it is assumed that the di-and triglycolated species of the hydroxylated cerium can also be neglected. Under these assumptions, equationThese values, when used to calculate values of k' are found to fit the experimental data only at the lower glycol concentration. Evaluation of equilibrium constants for the di-and triglycolated species is accomplished by trial and error. I t was found unnecessary to include the cubed power of glycol to fit experimental data. Selecting two higher values of k' at higher glycol concentrations and using the equationit was found that KB = 2.3 and km = 0.0117 sec.-l. In view of the uncertainties encountered in the experimental determination of pseudo rate constants, the values of rate constants and eauilibrium constants are assigned the limits (21) which is of the same form as equation (4) except for the modified subscripts and addition of the hydrogen dependency term. Aaain a t low alvcol concentrations (IG1 = 0.05). the diglycolated cornpiex concentrations may' be considered negligible. Using the value of k' from Part A, and the values of K,, k12K12, and [ H + ] , K12 = 15 and k,e = 0.0225 set.-'. kzz = AMES, IOWATABLE I1 0.09 4= 0.02 15 f 1 2 . 3 3t 0 . 4 0.0225 f 0.0010 see.-' 0.0117 i 0.0020 sec.-l RECEIVED MAY 21, 1951 [CONTRIBUTION NO. 520 FROM THE CHEMICAL LABORATORIES,

ULTRAVIOLET ABSORPTION SPECTRA OF SOME VINYLNAPHTHALENES AND RELATED AROMATIC HYDROCARBONS1, 2, 3

“…Observation of Fig. 1 shows that all of the 1-substituted naphthalenes studied, except V, have remarkably similar spectra with the principal absorption maxima at 225-226 m#i (A-band) and three secondary incompletely resolved maxima of intensities [ log < at Xmat. = ±0.1 for II-IV, VI, VII, IX and 0.1 to 0.2 (lower values for theirs) for I and VIII].…”

“…But the Xmax. and general shapes of the curves are essentially identical, except for some small loss of fine structure, with those of typical 1 -alkylnaphthalenes [cf. 1 -methylnaphthalene and 1 -cyclohexylnaphthalene (4)] and closely similar to that of 1 -phenylnaphthalene (4).…”

CHEMICAL REACTIVITIES OF ARYLCYCLOALKENES. II. POLAROGRAPHIC REDUCTION AND DIELS-ALDER CONDENSATION OF NAPHTHYL-1-CYCLOPENTENES AND NAPHTHYL-1-CYCLOHEXENES1, 2

“…The olefins I-IV were prepared and purified via the picrates in exactly the same manner as reported previously (1). Except for some minor variations in melting points (IV, 59-60°; II picrate, 76.5-77.5°; III picrate, 104-105°; IV picrate, 82-83°) and one variation in boiling point (II, 116°/0.3 mm.)…”

SOME VICINAL DISUBSTITUTED CYCLOPENTENES AND CYCLOHEXENES BEARING NAPHTHYL AND METHYL GROUPS1, 2

“…IB gave positive tests with DNP and NaOI and a negative test with Tollens' reagent. l-(2-Naphthyl)-l-cyclopentene (18) [formula III, Ri = Rz = H] used as a control sample for ozonolysis gave positive tests with Tollens' and DNP reagents (not tested with NaOI).…”

“…Values found for the molar percentage of aldehyde present (assuming pure dicarbonyl product were used) were IA, 30-50; IIA, 40; IIIA, 45-70; IVA, 40-65. Checks on benzaldehyde (used directly) and l-(l-naphthyl)-l-cyclohexene (18) [formula I, Ri = R2 = H] (oxidized as for IA-IVA) were 35-55% and 55-95%, respectively. Use of aqueous dimethylformamide in place of methanol or use of temperatures up to 85°did not improve the accuracy or reproducibility of the method.…”