Oxygen groups, review

Dimethyl a,a,a, a -tetracyano-2,5-diisopropyl-l,4-phenylenediacetate added at 70° to aq. 5%-KOH, stirred 1 min. until a soln. results, carefully acidified with 6 N HCl, and the solid treated with a slight excess of bromine water 2,5-diiso-propyl-7,7,8,8-tetracyanoquinodimethane. Y 86%. F. e. s. R. C. Wheland and E. L. Martin, J. Org. Chem. 40, 3101 (1975) electrically conductive charge transfer complexes with quinodimethanes and heteroethylenes such as heterofulvalenes s. Am. Soc. 98, 3916 (1976) comparison of 1,1-dinitrile with oxygen groups, review, s. K. Wallenfels et al., Ang. Ch. 88, 311 (1976) reactions of 7,7,8,8-tetracyano-quinodimethane, review, s. B. P. Bespalov and V. V. Titov, Russ. Chem. Rev. 44, 1091 (1975) (Engl, transl.). 

This review gives a brief presentation of the basic concepts and calculation methods of the "anionic group theory" for the NLO effect in borate crystals. On this basis, boron-oxygen groups of various known borate structure types have been classified and systematic calculations were carried out for microscopic second-order susceptibilities of the groups. 

A beneficial role of oxygen groups was also claimed for other metals. Suh et al. [12] showed that by using the hydrolysis by base of PdCh on both active carbons and carbon black, the Pd dispersion increases with increasing content of surface-oxygen groups. Please note that an extensive overview on the synthesis of supported Pd catalysts was given by Toebes et al. [17 and references therein]. In that review, attention was also paid to the use of carbon as a support. 

Mochida et al. (2000) reviewed the applicability of ACFs for the removal of SO and NO, . The highest activity for SO2 removal in the presence of water, at 25 °C, was achieved with pitch-based ACFs, and this activity could also be improved by heat treatment of the ACFs in nitrogen at temperatures ranging from 600 to 900 °C. For removal by reaction with ammonia, it was shown that the activity at room temperature of the ACFs was markedly increased if the ACFs were previously oxidized to form surface oxygen complexes. A mechanism was proposed on the basis of NO adsorption on the defect sites formed upon decomposition of surface oxygen groups, and subsequent oxidation to NO2, which reacts with adsorbed ammonia. 

Nitriles. Nitriles can be prepared by a number of methods, including ( /) the reaction of alkyl haHdes with alkaH metal cyanides, (2) addition of hydrogen cyanide to a carbon—carbon, carbon—oxygen, or carbon—nitrogen multiple bond, (2) reaction of hydrogen cyanide with a carboxyHc acid over a dehydration catalyst, and (4) ammoxidation of hydrocarbons containing an activated methyl group. For reviews on the preparation of nitriles see references 14 and 15. 

A single-crystal x-ray diffraction study has shown that the borate anion in anhydrous borax is polymeric in nature and is formed via oxygen bridging of triborate and pentaborate groups (83). The chemistry of anhydrous borax has been reviewed (73,84). 

It is convenient to classify here the decompositions of metal salts of the various oxyhalogen acids on the basis of the oxygen content of the anion, with subsections devoted to the metals of a particular sub-group of the Periodic Table. Again, consideration of the ammonium salts is deferred to Sect. 4. As noted elsewhere in this review, some reports are not explicit as to whether or not melting accompanies reaction thermal analysis studies can be valuable [843]. 

For a review of neighboring group participation by sulfinyl oxygen, see Montanari221. This special influence of sulfinyl groups on reactivity is, of course, due to the high polarity... 

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