The synthesis of quinoxaline and benzimidazole-N-oxides and of ester and amide derivatives of 3-hydroxy-2-quinoxalinecarboxylic acid by a novel process consisting of the reaction between a benzofuroxan and an activated methylene-containing compound under basic conditions.
general approach for the one-pot hydroaminomethylation of olefinsusing methylformate as formylating agent instead of synthesis gas (syngas) has been proposed. Herein we report that a Ru–Rh catalytic system demonstrates high activity in a tandem conversion of a series of n-alkenes into aminesusing methylformate with yields 58–92% (6 h). The selectivity for the normal amine reached 96% with catalysis by
Heterogeneous Ketone Hydrodeoxygenation for the Production of Fuels and Feedstocks from Biomass
作者:Rhodri W. Jenkins、Cameron M. Moore、Troy A. Semelsberger、Andrew D. Sutton
DOI:10.1002/cctc.201601678
日期:2017.7.24
conditions than have been reported previously for γ‐polyketone HDO. Stepwise HDO of the γ‐polyketone shows the reaction pathway occurs through ring‐closure to a saturated tetrahydrofuran species intermediate, which requires increased H2 pressure to ring‐open and subsequently to fully HDO. This work allows for further understanding of bio‐derived molecule defunctionalization mechanisms, and ultimately
在这项工作中,我们描述了一个简单的非均相催化系统,用于5-壬酮和2,5-己二酮的加氢脱氧(HDO),我们将其用作更复杂的生物质衍生分子的模型化合物。我们介绍了通过使用负载型金属和固体酸催化剂来逐步鉴定酮,以鉴定途中向烃类过渡的中间体。尽管在中等条件下(Ni / SiO 2 .Al 2 O 3,HZSM- 5、200 °C,1.38 MPa H 2,1 h)可以快速实现单酮HDO,但是定量的γ-聚酮HDO需要更高的压力和更长的反应时间(Pd / Al 2 O 3,HZSM-5、2.76 MPa H 2,5 h),尽管这些条件比以前报道的γ-聚酮HDO更容易。γ-聚酮的逐步HDO显示反应途径是通过闭环反应生成的饱和四氢呋喃类中间体,这需要增加H 2压力才能开环,然后达到完全HDO。这项工作可以进一步了解生物衍生的分子去功能化机理,并最终有助于促进生物质作为燃料和化学药品的原料。
The Simultaneous In-Situ Generation of Aldehydes and Phosphorus Ylides: A Convenient Multi-Step One-Pot Olefination Protocol
nucleophilic addn. of an organolithium reagent to DMF are basic enough to deprotonate alkyltriphenylphosphonium salts suspended in THF. The aldehydes, liberated by the spontaneous decompn. of the resulting a-amino alcs. (hemi-aminals), undergo a Wittig reaction with the simultaneously generated P ylides to afford olefins in excellent overall yields. This in situ method offers the unique advantage in
Li a-(二甲氨基)醇盐由亲核加成物产生。有机锂试剂对 DMF 的碱性足以使悬浮在 THF 中的烷基三苯基鏻盐去质子化。醛,由自发分解释放。产生的α-氨基醇。(半缩醛胺),与同时生成的 P 叶立德进行 Wittig 反应,以优异的总产率提供烯烃。这种原位方法在其适用于不稳定醛方面提供了独特的优势,否则这些醛将成为 (Z/E)-异构化或自缩合过程的牺牲品。[在 SciFinder (R) 上]
Catalytic Conversion of Cellulose to Liquid Hydrocarbon Fuels by Progressive Removal of Oxygen to Facilitate Separation Processes and Achieve High Selectivities
申请人:Dumesic James A.
公开号:US20100324310A1
公开(公告)日:2010-12-23
Described is a method to make liquid chemicals, such as functional intermediates, solvents, and liquid fuels from biomass-derived cellulose. The method is cascading; the product stream from an upstream reaction can be used as the feedstock in the next downstream reaction. The method includes the steps of deconstructing cellulose to yield a product mixture comprising levulinic acid and formic acid, converting the levulinic acid to γ-valerolactone, and converting the γ-valerolactone to pentanoic acid. Alternatively, the γ-valerolactone can be converted to a mixture of n-butenes. The pentanoic acid so formed can be further reacted to yield a host of valuable products. For example, the pentanoic acid can be decarboxylated yield 1-butene or ketonized to yield 5-nonanone. The 5-nonanone can be hydrodeoxygenated to yield nonane, or 5-nonanone can be reduced to yield 5-nonanol. The 5-nonanol can be dehydrated to yield nonene, which can be dimerized to yield a mixture of C
9
and C
18
olefins, which can be hydrogenated to yield a mixture of alkanes. Alternatively, the nonene may be isomerized to yield a mixture of branched olefins, which can be hydrogenated to yield a mixture of branched alkanes. The mixture of n-butenes formed from γ-valerolactone can also be subjected to isomerization and oligomerization to yield olefins in the gasoline, jet and Diesel fuel ranges.