F>-Cymene

Terephthalic acid has been obtained from a great many /)-disubstituted derivatives of benzene or cyclohexane by oxidation with permanganate, chromic acid, or nitric acid. The following routes appear to have preparative value from />-toluic acid, />-methylacetophenone,2 or dihydro-/)-tolualdehyde by oxidation with permanganate from f>-cymene by oxidation with sodium dichromate and sulfuric acid from />-dibromobenzene or from /i-chloro- or -bromobenzoic acid by heating at 250° with potassium and cuprous cyanides and from />-dibromo-benzene, butyllithium, and carbon dioxide. ... 

Boron trichloride, reaction with 2-aminobiphenyl, 46, 66 Boron trifluoride, in preparation of ni-tronium tetrafluoroborate, 47, 56 with hydrogen fluoride in isomerization of f-cymene to m-cymene, 47, 41... 

Table 3. ROMP of cyclooctene catalyzed by rutheniimi-arene complexes generated in situ from [RuCl2(f>-cymene)]2 and a NHC precursor in die presence of potassium tert-butoxide ...

Ruthenium(II)(ETA-6-F-cymene) complexes of poly(spirophosphazine pyridine) Characterisation of crosslinking [80]... 

The product is analyzed by vapor phase chromatography using a 6-ft., f-in. O.D. copper tube, packed with 5% Bentone-34 (Wilkins Instrument Co.) and 0.5% XF-1150 (General Electric Silicone Products) on Diatoport-S (80-100 mesh) (F and M Co.) flow rate of helium 60 ml./min., oven temperature 85°. This column separates m-cymene (retention time 12 minutes) from />-cymene (retention time 10 minutes) but does not resolve the ortho isomer. The purity of the distilled w-cymene is above 98%. 

Fig. 3.4. Hydrophobic anion effect on ise- The membrane contains valinomycin with equivalent concentration of potassium tetraphenyl-borate dissolved in 2-nitro-p-cymene. - ise dependence on the activity of KCl o - f jgg dependence on the activity of KCIO4. The curves were calculated using equation (3.3.13). (After W. E. Morf, G. Kahr and W. Simon.)...

Figure 10.2 UV/Vis spectra for (a) RuCb in ethanol, (b) Ru2(p-cymene)2Cl4 in CH2CI2, (c) 1 in CH2CI2, (d) the supported Ru complex 3, (e) the unsaturated Ru complex (5) activated by 02/iBA and (f) the supported Ru catalyst after 100 cycles of stilbene epoxidation. Spectra (a)-(c) were measured in a transmission mode (left-hand axis abs) and (d)-(f) in a diffuse reflectance mode (left-hand axis KM).

Lee s group has also reported ruthenium-catalyzed carbonylative cyclization of 1,6-diynes. The noteworthy aspect of this cyclization is the unprecedented anti nucleophile attack on a 7i-alkyne complex bearing a ruthenium vinylidene functionality. A catalytic system based on [Ru(p-cymene)Cl2]2/P(4-F-C6H4)3/DMAP was active for the cyclization of 1,6-diyne 103 and benzoic acid in dioxane at 65 °Cto afford cydohexenylidene enol ester 104a in 74% yield after 24h [34]. Additional examples are shown in Scheme 6.35. 

Fluoroacetophenone (1.2 mL, 10 mmol) was added, followed by [RUCI2 (p-cymene)]2 (30.6 mg, 0.05 mmol) and finally an additional 20 mL of 2-propanol. The mixture was stirred for 30 min at which time the reaction was quenched with diluted brine and extracted with ethyl acetate. The organic phase was filtered through a silica-pad (40 g), which was washed with ethyl acetate. The solvents were evaporated before column chromatography was performed over 100 g silica gel in a 7 cm diameter column, using penta-ne ethyl acetate 8 1 as eluent (yield 88%). The enantiomeric purity (97 % ee) was analyzed with GLC (CP Chiralsil DEX CB) 110 °C hold 10 min, rate 80 °C min to 200 °C and hold for 5 min. (/f-isomer) = 9.72 min and tR... 

Juniperus rigida Sieb. et Zucc. J. rigida Sieb. et Zucc. f. modesta (Nakai) Y. C. Chu Tu Soon (Juniper) (fruit) Alpha-pinene, myrcene, carene, limonene, p-cymene, beta-elemene, caryophyllene, humulene, bomeol, r-cadinene, terpinene, citronellol, anethole.48 Hemorrhage, treat hemoptysis, inflammation, kidney infection, arthritis joint infection. 

Lysimachia barystachys Bunge. L. christinae Hance L. clethroides Duby L. davurica Ledeb. L. davurica Ledeb. f. latifolia Korsh. Jin Qian Chao (Loosestrife) (whole plant) Essential oils, 1-pinocamphone, 1-menthone, 1-pinene, limonene, 1,8-cineol, p-cymene.33 Diuretic, a choleretic agent, antibacterial. 

Cymene Agastache rugosa, A. rugosa f. hypoleuca, Coriandrum sativum, Myristicafragrans m X... 

The heats of fusion and vaporization.—From the lowering of the f.p. of cymene and toluene by the soln. of liquid hydrogen chloride, E. Beckmann and P. Wantig14 calculate the heat of fusion of hydrogen chloride as 10 3 cals, per gram of hydrogen bromide, 7 44 cals. and of hydrogen iodide, 413 cals. D. McIntosh and B. D. Steele calculate from Clapeyron and Clausius equation d log pjdT—XjRT 2, for the mol. ht. 

PS-PMMA Mw = 640-150(1.24-69% PMMA-PS PMMA Mv — 110.50% Toluene -f p-tymene (selective for PS) Micellar shape transition as a function of toluene// -cymene mixture composition. SLS Kotaka el al (1978)... 

Mn02, cat [RuCl2(cymene)]2, cat 2,6-di-f-butyl-benzoquinone, cat K2C03 JOC 59 1196 (1994)... 

The sole coordination of the phosphine sites has also been observed with PBs featuring the flexible (CH2)2 linker. The coordination of ligands 40e and 40f to the [Ru(p-cymene)Cl2] fragment affords complexes 74a and 74b (Scheme 44). Despite the modest steric hindrance around boron, neither Cl-B (coordination mode F) nor Ru-B (coordination mode FI) interaction was found. Coordination mode E was established spectroscopically (8nB = 82 and 87 ppm for 74a and 74b, respectively) and confirmed crystallographically.55... 

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