Critical Solution Temperatures with Cyclic Hydrocarbons

Francis, Alfred W.

doi:10.1021/ie50420a005

Cited by 14 publications

(8 citation statements)

References 5 publications

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“…However, liquid-liquid immiscibility was observed in solutions of nitromethane with 1,2,4-trimethylbenzene (pseudocumene) at -31 °C and with 1,3,5-trimethylbenzene (mesitylene) at -16°C. The results are consistent with earlier reports (6, 7) of no immiscibility in these two solutions down to -20°C , but they do not agree with a report (2) of UCST of +1°C for nitromethane-1,2,4-trimethylbenzene solutions.…”

Section: Resultssupporting

confidence: 72%

Phase studies of some nitroalkane hydrocarbon mixtures

Clever¹,

Pirkle²,

Allen³

et al. 1972

J. Chem. Eng. Data

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Section: Resultssupporting

confidence: 72%

Phase studies of some nitroalkane hydrocarbon mixtures

Clever¹,

Pirkle²,

Allen³

et al. 1972

J. Chem. Eng. Data

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“…monophasic conditions) above 80 °C. The biphasic reaction mixture was heated above the critical mixing temperature59 and the reaction was allowed to proceed for the specified period of time after which it was cooled to room temperature whereupon phase separation occurred. Each reaction was repeated five times in the biphasic solvent mixture with a single batch of catalyst added prior to the first cycle (Figure 1).…”

Section: Resultsmentioning

confidence: 99%

Homogeneous Catalysts Supported on Soluble Polymers: Biphasic Sonogashira Coupling of Aryl Halides and Acetylenes Using MeOPEG‐Bound Phosphine–Palladium Catalysts for Efficient Catalyst Recycling

Köllhofer

Plenio

2003

Chemistry A European J

144

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The Sonogashira coupling of various aryl bromides and iodides with different acetylenes was studied under biphasic conditions with soluble, polymer-modified catalysts to allow the efficient recycling of the homogeneous catalyst. For this purpose, several sterically demanding and electron-rich phosphines of the type R(P)PR(2) were synthesised. They are covalently linked to a monomethyl polyethylene glycol ether with a mass of 2000 Dalton (R(P)=MeOPEG(2000)) R(P)PR(2): -PR(2)= -CH(2)C(6)H(4)CH(2)P(1-Ad)(2), -C(6)H(4)-P(1-Ad)(2), -C(6)H(4)-PPh(2). To couple aryl iodides and acetylenes, the catalyst [(MeCN)(2)PdCl(2)]/2 R(P)-C(6)H(4)-PPh(2) was used in CH(3)CN/Et(3)N/n-heptane (5/2/5). The combined yields of coupling product over five reaction cycles are between 80-95 percent. There is no apparent leaching of the catalyst into n-heptane, as evidenced by (1)H NMR spectroscopy. The new catalyst [(MeCN)(2)PdCl(2)]/2 (1-Ad)(2)PBn can be used for room-temperature coupling of various aryl bromides and acetylenes in THF with HNiPr(2) as a base. A closely related catalyst Na(2)[PdCl(4)]/2 R(P)-CH(2)C(6)H(4)CH(2)P(1-Ad)(2) linked to the polymer was used to couple aryl bromides and acetylenes in DMSO or DMSO/n-heptane at 60 degrees C with 0.5 mol percent Na(2)[PdCl(4)], 1 mol percent R(P)PR(2) and 0.33 mol percent CuI. The combined yield of coupling products over five cycles is always greater than 90 percent, except for sterically hindered aryl bromides. The determination of the turnover frequency (TOF) of the catalyst indicates only a small decrease in activity over five cycles. Leaching of the catalyst into the product containing n-heptane solution could not be detected by means of (1)H NMR and TXRF; this is indicative of >99.995 percent catalyst retention in the DMSO solvent.

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“…Data Series V/1, 2, 3, 1979-1980). More than 6,000 critical solution temperature observations are listed by Francis (1961Francis ( , 1963 and more than 300 involve water as one of the solvents.…”

Section: Properties Of Solvent Systems With a Critical Point Of Miscimentioning

confidence: 99%