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The hydrothermal experiments with ketones and formic acid showed that the hydrogen transfer reduction of ketones can be conducted using formic acid as a hydride donor in the presence of NaOH at 300 ℃. The yield of alcohols was considerably higher at a much lower ratio of hydrogen source to ketones than the traditional Meerwein-Ponndorf-Verley (MPV) reduction, reaching 60% for isopropanol from acetone and 70% for lactic acid from pyruvic acid. Water molecules may act as a catalyst in the hydrogen transfer reduction of ketones under hydrothermal conditions.  相似文献   
2.
本文以自制的邻氯二苯醚为改性第三单体,使之与对策二甲酰氯(TPC),二苯醚(DPE),在无水AlCl3/l,2-二氯乙烷/Lewis碱催化溶剂体系中进行三元无规共缩聚,制得一系列含侧基氯取代的聚芳醚酮酮(Cl-PEKK),并对它们进行了分析表征。  相似文献   
3.
《文物保护研究》2013,58(4):217-226
Abstract

Many natural and synthetic products have been used for the consolidation of paint layers, but none have been thoroughly tested for this application. This is apparent for most of the synthetic and semi-synthetic adhesives for conservation, many of which are pure polymer resins and dispersions adapted from other industries. They were not specifically formulated with the appropriate properties for conservation, nor do they take advantage of some of the more recent developments in adhesive technology. BEVA® 371 is unique among adhesives used for consolidation treatments, as it is a multi-component mixture and was designed specifically for the conservation field using the best technology available at the time. However, the main focus of the research was its application as a lining adhesive. Thus, optical properties and stability, specifically color stability, were not thoroughly evaluated even though some lining applications that were first recommended could have benefited from this type of investigation. This paper will discuss the development of BEVA® 371, the chemistry, and roles of each component, and address a practical concern about the tack behavior of its replacement formulation, BEVA® 371b.  相似文献   
4.
The hydrothermal experiments with ketones and formic acid showed that the hydrogen transfer reduction of ketones can be conducted using formic acid as a hydride donor in the presence of NaOH at 300℃. The yield of alcohols was considerably higher at a much lower ratio of hydrogen source to ketones than the traditional Meerwein-Ponndorf-Verley (MPV) reduction,reaching 60% for isopropanol from acetone and 70% for lactic acid from pyruvic acid. Water molecules may act as a catalyst in the hydrogen transfer reduction of ketones under hydrothermal conditions.  相似文献   
5.
Sm/TiCl4 system could well integrate the high reactivity of samarium(Ⅱ) and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupling reactions of ketones with esters mediated by metallic samarium (Sm) and a catalytic amount of titanium tetrachloride (TiCl4) were successfully developed. A series of substituted ketones and cyclic β-keto-esters were prepared in moderate to good yields under reflux and neutral conditions.  相似文献   
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