Search

We investigated the surface tension and surface composition of various mixtures of the two ionic liquids (ILs) 1-methyl-3-octyl-imidazolium hexafluorophosphate [C8C1Im][PF6] and 1,3-bis(polyethylene glycol)imidazolium iodide [(mPEG2)2Im]I in the temperature range from 230 to 370 K under ultraclean vacuum conditions. The surface tension was measured using a newly developed apparatus, and the surface composition was determined by angle-resolved X-ray photoelectron spectroscopy (ARXPS). In the pure ILs, the alkyl chains of [C8C1Im][PF6] and the PEG chains of [(mPEG2)2Im]I are enriched at the IL/vacuum interface. In the mixtures, a strong selective surface enrichment of the alkyl chains occurs, which is most pronounced at low [C8C1Im][PF6] contents. For the surface tension, strong deviations from an ideal mixing behaviour take place. By applying a simple approach based on the surface composition of the mixtures as deduced from ARXPS, we are able to predict and reproduce the experimentally measured temperature-dependent surface tension values with astonishingly high accuracy.

2-Arylamino-3-pyridinecarbonyl chlorides acylated the β-carbon atoms of enamines, and the resulting enaminones cyclized to give a series of fused polycyclic N-aryl pyridones. The series included 10-(3-chlorophenyl)-6,8,9,10-tetrahydrobenzo[b][1,8]naphthyridin-5(7H)-one (Sch 40120), an antipsoriatic agent.

Ammonium formate in the presence of palladium on carbon in methanol reacted with (S)-(+)4-(2-Amino-3-chloropropyl)-imidazole to give optically pure (R)-(−)-α-methyl histamine at atmospheric pressure.

The structural modification of the benzylic ether region of oxime 1 has resulted in the identification of several novel aryl amides as selective or dual NK 1 /NK 2 antagonists.

N-Oxidation of 2-methyl-3β-phenyl-2,3α,3aβ,6aβ-tetrahydrothieno [2,3-d] isoxazole-4,4-dioxide (1) gave a nitrone (2) which underwent an intramolecular 1,3-dipolar cycloaddition yielding a tricyclic isoxazolidine (4). A single-crystal X-ray analysis unequivocally established the structure of 4 as 9β-phenyl-2-oxa-6-thia-1-azatricyclo[3.3.1.03,7]nonan-4α-o1-6,6-dioxide. LiA1H4 and LiA1D4, reduced 4 exhaustively and rearranged it profoundly to isotopomers 5 and 6, respectively ; a novel Grob fragmentation may have mediated the rearrangement. Inter alia, measurements of 13C-13C coupling constants and of m z ratios of fragment ions yielded the complete structures of 5 and 6. They are 5β-phenyl-8-thia-6-azabicyclo[3. 3. 1]octan-2α-o1 and its 3α-deuterio analog, respectively.