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By Reductive Processes

Reduction of 2-methoxycarbonylpyrazine in tetrahydrofuran with lithium aluminum hydride at about — 70° gave 2-formylpyrazine (46%), but reduction of 2-chlorocarbonylpyrazine with lithium tri-r-butoxyaluminohydride in tetrahydrofuran gave 2-(pyrazin-2-ylmethoxycarbonyl)pyrazine (55%) and 2-formylpyrazine (20%) (1077), and 2-ethoxycarbonyl-3-methylpyrazine was reduced with lithium aluminum hydride in tetrahydrofuran at — 70° to 2-formyl-3-methylpyrazine (1185). [Pg.295]


Senzaki T. and Kumagai Y. (1988) Removal of chlorinated organic compounds from wastewater by reduction process II. Treatment of trichloroethylene with iron powder. Kogyo Yosui 357, 2-7. [Pg.158]

Photocatalysis is mostly thought of in terms of the photodegradation of molecules initiated either by oxidative or by reductive processes. However, photosynthesis may also result from a photocatalytic process, as observed for the reduction of C02 to formic acid by natural minerals. This reaction is the first step in an abiotic pathway for the synthesis of organic molecules and has been proposed to have played a role in the origin of life on earth [9]. [Pg.57]

EPR spectroscopy data indicate that structural transformations observed in the activated Li0H+V20s mixture as well as after its heating or ageing are accompanied by reduction processes. [Pg.107]

Using the approach of the Russian school,the syntheses of 2,4-dimethoxy- and 2,3,4-trimethoxy-oestra-l,3,5(10)-trien-17)S-oU have been developed (Scheme 7). Condensation of 2-methoxy-6-lithionaphthalene (102) with the substituted cyclopentanone (103) afforded the dicarboxylic acid (104). Ring closure gave the tetracyclic derivative (105). Catalytic hydrogenation yielded either the 11-keto-compound (106) or the 11-deoxy-derivative (107), depending on the nature of the catalyst. The 11-keto-compound (106) was subsequently converted into the corresponding oestratriene derivative (108) by reductive processes. [Pg.349]

The chief chemical use of such nitrates has arisen from opportunities to take advantage of their stability, the easy, selective removal of the nitrate groups from certain positions, and their ready and complete denitration by reductive processes. These properties have permitted preparation of several new methyl ethers of D-glucose, D-galactose, and D-fructose. ... [Pg.135]

Nitrate ion can be another effective nucleophile for inversion. It has been demonstrated that, due to the low basicity of the nucleophile, the competing elimination reaction is almost completely suppressed and the resulting nitro esters can be readily converted into alcohols by reductive processes. One serious... [Pg.22]

In addition, degradation of 2,3,7,8-TCDD in basic solutions of polyethyleneglycol and oxidants actually appears to occur by reductive processes, since the products are the lower chlorinated dioxins... [Pg.86]

Chromium (Cr) toxicokinetic is the toxicokinetics of two different oxidation states, Cr(III) and Cr(VI), linked by reduction processes that are ubiquitous in body fluids and tissues. The kinetic behaviors of these two major oxidation states of chromium are very different. Reduction of Cr(VI) to Cr(III) in the body, the lung, and the gastrointestinal tract is sufficiently rapid that bulk chromium kinetics may be considered to be the kinetics of Cr(III). However, certain detectable differences in chromium disposition depend upon whether exposure is to a Cr(III) or a Cr(VI) salt. In addition, the reduction process itself is of interest relative to the carcinogenicity of Cr(VI) in the lung. Therefore, a comprehensive understanding of the toxicokinetics of chromium must include the disposition of both Cr(III) and Cr(VI). [Pg.215]


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Characteristic of reduction processes by pure H2 in catalyst bed

Characteristic of reduction processes by syngas in catalyst bed

Enamines by Reductive Processes

Reduction process

Reduction processing

Reductive processes

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