Methanimines, acidity

CH3I (methyl iodide) principal axes, 103 If rotation, 113 CH2NH (methanimine) interstellar, 120 Cr203 (chromium trioxide) in alexandrite laser, 347ff in ruby laser, 346ff HC3N (cyanoacetylene) interstellar, 120 HCOOH (formic acid) interstellar, 120 NH2CN (cyanamide) interstellar, 120... 

Polymerizations of S and MMA with in situ catalyst formation have also been carried out. Matyjaszewski et a ..355 reported on the use of FeBr2 together with various ligands such as PfQHs). , NiCiIIo. and 133 alone or in combination. The use of diearboxylic acid (iminodiacetic acid, isophthalic acid)356 and methanimine ligands " for MMA polymerization has also been reported. 

The thermal decomposition of 2-azidoacetic acid (N3CH2CO2H) in the vapour phase has been shown, by photoelectron and matrix isolation infrared spectroscopy, to involve simultaneous formation of CO2 and methanimine (CH2NH) with concerted ejection of N2.52 No evidence was found for formation of intermediate nitrene (NCH2CO2H) or the imine (HNCHCO2H) to which it could be converted by 1,2-hydrogen shift. 

Isobarbituric acid 2,4,5(3//)-Pyrimidinetrione, dihydro- Methylenimine Methanimine... 

Very few syntheses of tetrazoles were reported in 2003. Various a-dialkylated (3-keto esters 219 underwent Schmidt rearrangement with trimethylsilyl azide to give tetrazole 220, which could be elaborated further to azido acid 221, precursors to a-dialkylated a-amino acids <03TL3179>. Di(benzotriazolyl)methanimine 222 reacted with various secondary amines to generate 223, which when treated with sodium azide in the presence of acetic acid yielded N,N-disubstituted 5-aminotetrazoles 224 in moderate to good yields <03JOC4941>. 

The acid-catalyzed reaction of methanimines with /3-substituted enamines, utilized for the preparation of symmetrical 3,5-disubstituted pyridines29a [Eq. (10)], has been carefully investigated and shown to proceed by in situ generation and subsequent [4 + 2] cycloaddition of electrophilic 1-aza-l,3-butadienes with the electron-rich enamine.29b Additional studies have reduced this process to a controlled [4 + 2] reaction of the isolated /V-terf-buty 1-1 -aza-1,3-butadienes with enamines or related electron-rich olefins including ketene O.Af-acetals290 [Eq. (11)]. 

Amaud et al performed a detailed study of the addition of HCN to methanimine in the gas phase, which is the key step of one of the most realistic processes suggested for the prebiotic synthesis of amino acids. A wealth of BCP properties is monitored during the process of bond making and breaking. 

The imine-ene reaction has been studied by DFT for the model case of methanimine, H2C=NH, and propene a wide range of catalyses by Lewis acids are covered. ... 

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