4088-22-6Relevant articles and documents
Cleft Formation upon Polymerization of Surfactant Vesicles
Nome, Faruk,Reed, Wayne,Politi, Mario,Tundo, Pietro,Fendler, Janos H.
, p. 8086 - 8093 (1984)
Morphological consequences of the photopolymerization of vesicles prepared from (C18H37)2N+(CH3)CH2C6H4-p-CH-=CH2*Cl-, 1, have been investigated by using 8-hydroxy-1,3,6-pyrenetrisulfonate (POH) as a reporter group.Static and dynamic laser light scattering established the hydrodynamic radius and the molecular weight of 1 vesicles to be 425 +/-25 Angstroem and 2.3E7.Neither of these values changed upon polymerization.POH was shown to bind appreciably to 1 vesicles.Excitation of POH, following immediately its addition to nonpolymerized 1 vesicles, resulted in fluorescence emission with maxima at 440 and 520 nm.Incubation led to time-dependent changes of this spectra.Increasing incubation time of POH containing nonpolymerized 1 vesicles resulted in the gradual disappearance of the emission band at 520 nm and in the concomitant increase of the emission band at 440 nm.Fluorescence spectra of POH did not show any time-dependent changes following its addition to polymeryzed 1 vesicles.These results were interpreted in terms of the gradual penetration of POH into nonpolymerized 1 vesicles and in terms of long-term stabilization of POH in the clefts formed on the vesicle surface upon pulling the surfactant head groups together by photopolymerization.Differences between nonpolymerized and polymerized vesicles also manifested in the excited state protonation equilibria (POH)* (PO-)* + H+.A koff8 value of 4.3E9 s-1 was obtained in nonpolymerized vesicles immediately after the POH injection.Following a day of incubation no excited-state proton ejection could be observed in nonpolymerized 1 vesicles.Consequently, a koff* value of 6.1E9 s-1 was observed in nonpolymerized vesicles both immediately and 1 day subsequent to the addition of POH to polymerized 1 vesicles.Similar behavior has been observed for the steady-state (P) and nanosecond time-resolved polarizations, τR values, of POH, as well as that for the ground state PO- reprotonation (governed by Kon) in nonpolymerized and polymerized 1 vesicles.In nonpolymerized 1 vesicles, P values increased (from 0.12 to 0.19), τr was determined to be >/= 50 ns, and kon values (4E8 M-1 s-1) became unobservable after a day of incubation.In polymerized 1 vesicles, P values of 0.08, values τR of 4 ns, and kon values 8E8 M-1 s-1 remained unaffected by incubation.
METHOD FOR PRODUCING NITROGEN-CONTAINING COMPOUND
-
Page/Page column 10, (2008/12/09)
The present invention provides a process for producing high-purity aliphatic tertiary amines containing a less amount of by-products by subjecting aliphatic acid amides to hydrogenation reduction under moderate conditions, as well as a process for producing amine derivatives from the aliphatic tertiary amines, with a good productivity in an economically advantageous manner. The present invention relates to a process for producing an aliphatic tertiary amine by subjecting a specific aliphatic amide to hydrogenation reduction in the presence of a catalyst containing copper and at least one element selected from the group consisting of elements belonging to Groups 2, 3 and 7 of the Periodic Table; the catalyst; and a process for producing amine oxide by reacting the tertiary amide obtained by the above production process with hydrogen peroxide.
Chemical Differentiation of Bilayer Surfaces in Functional Dialkylammonium Ion Vesicles: Observation of Surfactant Flip-Flop
Moss, Robert A.,Bhattacharya, Santanu,Chatterjee, Swati
, p. 3680 - 3687 (2007/10/02)
Cationic p-nitrophenyl carbonate and p-nitrophenyl benzoate functionalized di-n-octadecylmethylammonium ion surfactants 6 and 7 were synthesized.Vesicles of 6 or covesicles of (1:9) 7 and 5, created at pH 3.9, gave rapid, partial p-nitrophenylate cleavage at pH 7.9-8.0 (from 6) or rapid, partial benzoate cleavage by external thiolate ions at pH 7.9-8.0 (from 7), attributed to surface-specific exovesicular reactions of 6 or 7/5.These exovesicular cleavages at pH 8 and 25 deg C are apparently faster than reagent permeation across the bilayers to the endovesicularfunctional groups at pH 3.9.The dioctadecylammonium ion vesicles, in contradistinction to their dihexadecyl analogues, are able to maintain the indicated pH gradient long enough at 25 deg C to permit the surface-specific esterolyses.Relaxation of the pH gradient and endovesicular cleavages follow upon enhancement of the fluidity of the vesicle bilayers either with the application of heat or with additives such as 1-hexanol or dioctyldimethylammonium chloride.In the surface-differentiated 7/5 covesicles, "flip-flop" of intact 7 from endovesicular to exovesicular sites can be promoted and visualized by experiments that involve incubation of the vesicles at 38-40 deg C, pH 3.9, for 1-12 min.
