Yamazaki reaction

In the present work, monomers (e.g., V) hawing preformed amide linkages (as in II and IV) have been used in the Yamazaki reaction... 

Polymerization. Monomers V and VI were polycondensed at 100°C using standard Yamazaki reaction conditions. A copolymer was prepared in a similar manner by polymerization of equimolar amounts of V and VI [8]. VI also was copolymerized [9] with different amounts of -arainobenzoic acid (PAB) to yield PBA copolymers having varying degrees of N-raethyl amide substitution. The several polymers, with their mole percent N-methyl PBA contents and Inherent viscosities, are given in Table II. 

The PBA produced from monomer V has the highest inherent viscosity reported to date for any PBA prepared via the Yamazaki reaction. The reason for this probably lies in the... 

The preparation of amides via the free acid, diamine and catalysts, is also referred to as the Yamazaki reaction. Organic phosphor containing compounds, such as triphenyl phosphite are used as catalysts. In addition, in NMP/pyridine solvents, salts such as LiCl and CaCl2 are dissolved that favor polymerization. 

Isocyanide insertion and related reactions. Y. Yamamoto and H. Yamazaki, Coord. Chem. Rev., 1972,8,225-239 (47). 

Yamamoto and Yamazaki also suggest that the higher steric requirements of tert-h xty and 2,6-dimethylphenyl isocyanides determine the lack of an acylimino-nickel complex in their reactions with C5H5Ni(PPhj)CH3 (166). 

Yamamoto and Yamazaki 171) carried out reactions of Pt(PEt3)2CHjI and Pt(PPhMe2)(CH2CjH5)I with tert-butyl and cyclohexyl isocyanides. These reactions gave small yields of the ionic intermediate species, which readily reverted to the appropriate iminoacyl complexes. In reactions of analogous chloride complexes the intermediate species was not isolated. It is suggested on the basis of PMR data that these iminoacyl complexes are five-coordinate (see above). 

Ogura, Y. and Yamazaki, I. (1983). Steady-state kinetics of the catalase reaction in the presence of cyanide. J. Biochem. (Tokyo) 94, 403-408. 

Watanabe, T., Akiyama, H., Yamakawa, H., lijima, K., Yamazaki, F., Matsumoto, T., Futo, S., Arakawa, F., Watai, M., and Maitani, T. (2006). A specific qualitative detection method for peanut (Arachis hypogaea) in foods using polymerase chain reaction. /. Food Biochem. 30, 215-233. 

Yamazaki, Kondo and coworkers [78] reported on a combination of a Heck reaction and an animation on solid phase for the synthesis of indole carboxylate 6/1-148, employing an acetylated immobilized enamide 6/1-145 and a bifunctionalized... 

T. Odajima and I. Yamazaki, Myeloneperoxidase of the leukocyte of normal blood. 3. The reaction of ferric myeloperoxidase with superoxide anion. Biochim. Biophys. Acta. 284, 355-359 (1972). 

A successful selective head-to-tail telomerization to give 1-methoxy-2,6-dimethyl-2,7-octadiene (89) by the reaction of isoprene with methanol at room temperature was reported by Yamazaki (59). Although the reaction is the selective head-to-tail addition, unfortunately the methoxy group was introduced at the position opposite to oxygen function in natural products ... 

SUH, D.-Y., FUKUMA, K., KAGAMI, J., YAMAZAKI, Y., SHIBUYA, M., EBIZUKA, Y., SANKAWA, U., Identification of amino acid residues important in the cyclization reactions of chalcone and stilbene synthases, Biochem. J., 2000,350, 229-235. 

Transition metal mediated or catalyzed benzene formation reactions have been reported using various metals. However, the use of three different alkynes is difficult [38], In many cases, a mixture of several benzene derivatives is obtained. In 1974, Wakatsuki and Yamazaki used three different alkynes with Co complexes [27b], but isomers were formed and a tedious chromatographic separation was necessary. The first selective coupling of three different alkynes in high yields was reported in 1995 using a combination of unsymmetrical zirconacydopentadienes and CuCl, as shown in Eq. 2.52 [7k]. 

Under this approaeh, one of the biggest question is if the reaction (19) is not to slow to compete with the reaetion (18). On the other hand, Fe appears to be a weaker oxidant than OH radieal Koppenol and Liebman 1984 Rahhal and Richter 1988). Experimental evidences (using the electron paramagnetic resonance spin-trapping method) have shown the existence of several intermediated oxidant in the Fenton proeess, like OH bound OH and high-valence iron speeies Yamazaki and Piette 1991 De Laat and Gallard 1999 Gallard and De Laat 2001). 

Table 6.4 Effect of the molecular weight of poly(vinyl pyrrolidone), PVP, on the polycondensation reaction of L-leucine. [Reprinted from N. Yamazaki and F. Higashi, Adv. Polym. Sci., 38,1 (1981)]...

K. Yamazaki H. Tokui, The Cross-Linking Reaction of Polybutadiene Binder for Composite Propellants , BullChemSocJapan 38 (12). 2774-78 (1965) (English) CA 64, 6391 (1966)... 

Yasuo Yamazaki and Tadashi Kawai Metal-Catalyzed Cyclization Reactions of Hydrocarbons Zoultan Paal... 

Kirsch-De-Mesmaeker A, Lecomte J-P, Kelly JM (1996) Photoreactions of Metal Complexes with DNA, Especially Those Involving a Primary Photo-Electron Transfer. 177 25-76 Kirschning A, Bechthold A F-W, Rohr J (1997) Chemical and Biochemical Aspects of Deoxy-sugars and Deoxysugar Oligosaccharides. 188 1 - 84 Kitazume T.Yamazaki T (1997) Enzymatically Controlled Reactions of Organofluorine Compounds. 193 91 -130... 

We have previously seen (p. 242) that reactions between two excited molecules are extremely rare, " Yamazaki Cvetanovit, Ref. 967 Yamazaki Cvetanovii Irwin J. Am. Chem. Soc. 1976, 98, 2198. For other likely examples, see Lewis Hoyle Johnson J. Am. Chem. Soc. 1975, 97, 3267 Lewis Kojima J. Am. Chem. Soc. 1988, 110, 8660. 

Yamazaki, I. Free radicals in enzyme-substrate reactions. In Free Radicals in Biology. Vol. II (Pryor, W. A., ed.). New York-San Francisco-London, Academic Press, 1977, pp. 183-218... 

Horiuti Nakamura [75] have considered the possibility that there may be more than one set of stoicheiometric numbers leading to an overall reaction between the species s s. They find that the number of such reaction routes is the row nullity of the matrix [a ]. Nakamura has also considered the affinity of the overall reaction near equilibrium [79] and with Yamazaki [20] has related this to the theorem of minimum entropy production. 

Sherlin and Velichkin191 reported that the reaction of 2-aminopyridine and I-bromo-3-chloropropane afforded the 3,4-dihydro-2H-pyrido[l,2- ]-pyrimidine (135) in 23 yield. Later Yamazaki et al.ig2 prepared the same product (135) from 2-chloropyridine and 3-aminopropanol via intermediates 133 and 134. 

Mannanase. Sprucewood delignified at room temperature was treated with mannanase as described by Yamazaki (15). However, a higher mannanase concentration was used, and the reaction was followed by means of quantitative, column chromatographic analysis of the reducing sugars in the reaction solutions. 

The experiments were repeated under similar conditions with the same and another mannanase fraction of Yamazaki s, with sprucewood holocellulose prepared in a slightly different way (19). After three weeks incubation, about 19% of the mannan was dissolved away, and the loci of hemicellulose removal were revealed by electron microscopy. In these experiments, the bulk of hemicelluloses was obviously removed by the buffer solution. In addition to mannose, glucose and galactose derived from mannan, xylose and glucose were found in the reaction solutions in appreciable amounts. 

Shoko Yamazaki was born in Osaka, Japan. She studied chemistry at Osaka University and received her Ph.D. in 1986 under the supervision of Prof. Ichiro Murata. From 1985, she was an assistant lecturer at Nara University of Education. She joined the group of Professor Barry M. Trost as a visiting researcher at Stanford University (USA) in 1987-88. She became an assistant professor at Nara University of Education in 1989 and since 2003, a full professor of Nara University of Education. Her current main research interests are the development of new organic synthetic reactions. 

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