Amine sensitization

The fluorescence spectra of tris- and tetrakis-diketonato Eu and Eu complexes have been studied, and the amine sensitization of the fluorescence of (1 Ln = Eu, R = R = Ph) has been investigated. Trimethyldioxetan, on thermal decomposition in the presence of [Eu(tta)3(o-phen)], gives narrow band chemiluminescence. 

A lot of biologic membrane systems and cellular organelles contain kinases, which transfer phosphate groups to proteins, especially to serine, threonine, and tyrosine residues. Self-phosphorylation of enzymes leading to acylphosphates or phosphoamides can be observed, too. With respect to their chemical stability, these phos-phoproteins are classified into acid-stable (alkali labile), hydroxyl-amine-sensitive, and acid labile. 

Yinon et al. (228) used an HPLC interfaced with a triple-quadrupole mass spectrometer by means of a particle beam for the identification of several azo dyes. Characterization of the dyes was achieved by observing typical fragment ions formed by cleavage of the N-C and C-N bond on either side of the azo linkage and/or cleavage of the N=N double bond with the transfer of two hydrogen atoms to form an amine. Sensitivity was observed to be two to three orders of magnitude worse than with thermospray ionization. 

Charge reversal in the electron transfer can be observed if donor sensitizers are employed. For example, photosolvolysis of cyclohexene oxide (135), may proceed through the epoxide radical anion. Analogous fragmentation from stilbene oxide and extrusion of SC>2 from benzylsulfone has been reported when amine sensitizers are employed (136). In fact, reductive electron transfer to cyclic sulfites or carbamates, eq. 49 (137),... 

Evidently the a-H is likely to be involved in the early stages of the decomposition process [16], perhaps moving to an adjoining nitro group to form a nitronic acid tautomer, 4 [35,45,46]. These are known to be reactive and unstable [47], The transfer or loss of a proton to yield a nitronic acid or a nitronate (aci) anion has also been invoked as the initial step in the decompositions of other energetic molecules, e.g. picric acid [35,48] and amine-sensitized nitromethane [49-51]. 

T. Katsu, et. al.. Amino acid analysis using amine-sensitive membrane electrodes. Anal. Chim. Acta. 239 (1), 23-7 (1990). 

Using ammonium salts as the sensitizer for nitromethane-based explosives appears to be an advantageous approach. First of aU, ammonium salts usually are not very toxic, thus they would not impose toxicity-related health risks on operation staffs. Second, unlike amine sensitizers that often lead to damaged explosive properties, the explosion properties of nitromethane with ammonium salt sensitizers are almost the same as plain nitromethane. Detonation distance of nitromethane with different sensitizers was shown in Table 7.6. 

Linthicum DS, Munoz JJ, Blaskett A. Acute experimental autoimmune encephalomyelitis in mice. I adjuvant action of bordetella pertussis is due to vasoactive amine sensitization and increased vascular permeability of the central nervous system. Cell Immunol 1982 73(2) 299-310. 

Moreover, a study has been made on the effect of fluorine substitution in the MBH reaction of various fluorocarbonyl partners with acrolein, methyl vinyl ketone, ethyl acrylate and acrylonitrile. Multifunctionalized fluorinated allyl alcohols were prepared from amine-sensitive aldehydes and olefins by balancing their reactivities. When the olefin is capable of reacting with itself in the presence of an amine e.g. acrolein), the electrophile has to be very reactive as well e.g. fluoral) to obtain a modest to good yield of MBH products. The reaction of a moderately reactive olefin e.g. ethyl acrylate or acrylonitrile) and a very reactive electrophile e.g. fluoral) resulted in self-reaction of the electrophile or very low yield of the allylic alcohol product. 

Boga, R. MacDonald, J. G. Personal hygiene products containing liners of amine-sensitive dyes as indicators of vaginitis. U.S. Pat. Appl. Publ. US 2005124072, 2005 Chem. Abstr. 2005,143, 13472. Mizutani, T. Noda, N. Method of detecting viable cells by fluorescent staining. Eur. Pat. Appl. EP 1624071, 2006 Chem. Abstr. 2006,144, 187557. 

Ramaswamy, A. L. Mukundan, T. Chaudhri, M. M. Amine sensitization studies of secondary explosives nsing laser-indnced ignition. J. Propulsion Power 2001,17, 163-168. 

A seminal example of a biomimetic material for discrimination by polarity was described by Lin and coworkers in 2001. The authors functionahzed the inner walls of the pores of an MCM-41 solid with an amine-sensitive o-phthalic hemithioacetal. Subsequently, the pores were cofunctionalized with several groups (propyl, phenyl, and pentafluorophenyl) in order to tune their polarity (Figure 19). The extraction of certain amines into the pores... 

If this has a AV of -20 cc/mole one can very crudely estimate aci ion concentrations of 10" to 10 M at pressure conditions adequate to initiate homogeneous nitromethane. The aci ion is a very reactive species. It is known to be a good nucleophile, a precursor to fulminic acid, and a facile electron transfer agent. If these very small amounts of an intermediate are kinetically competent to bring about the violent exothermic decomposition of nitromethane it must indeed be very reactive. This is the basis for the arguments related to the amine sensitization of nitromethane [39]. Does one then view the C-H bond in nitromethane as the trigger linkage ... 

Since it is metal mediated, the reactions could be carried out at low temperatures, and were complete within 15 h-2 d. Amine sensitive substrates, such as fluoral and 1,1,1-trifluoroacetone, also underwent reaction to provide the products in good yields. However, we obtained the product allyl alcohols in only 15-43% ee (Scheme 19) (Rudd, M. T. Reddy, M. V. R., unpublished results). We did not attempt to determine the configurations of these allylic alcohols due to their low ee. 

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