Reaction of Naphthalene and Its Derivatives with Hydroxyl Radicals in the Gas Phase
摘要:
Naphthalene is the most abundant polycyclic aromatic hydrocarbon (PAH) found in urban air. It is reactive in the atmosphere under ambient conditions, its chief reaction partner being the hydroxyl radical, OH.. In this work, the reactions of OH. with naphthalene, 1- and 2-naphthol, and 1- and 2-nitronaphthalene were studied in a 9.4 m(3) smog chamber. Relative rates of reaction accorded well with previous studies and allowed estimates to be made of the atmospheric lifetimes of these compounds. Numerous oxidation products were identified, and mechanisms proposed for their formation were based on the further transformation of benzocyclohexadienyl radicals formed by addition of OH. to naphthalene. The naphthols and nitronaphthalenes were deduced not to be on the major reaction pathway to the more oxidized products. Because of the high reactivity of PAH in air, we suggest that priority be given to identifying and quantitating their reaction products, some of which may be relatively persistent air toxics.
A process for preparing lacidipine, comprising reacting a t-butoxy carbonyl methyl aryl phosphonium halide with o-phthalaldehyde, and further reacting a product comprising (E)-3-(2-formylphenyl)-2-propenoic acid, 1,1-dimethyl ethyl ester, without isolation, with ethyl-3-amino crotonate.
Asymmetric Photocatalysis by Intramolecular Hydrogen‐Atom Transfer in Photoexcited Catalyst–Substrate Complex
作者:Chenhao Zhang、Shuming Chen、Chen‐Xi Ye、Klaus Harms、Lilu Zhang、K. N. Houk、Eric Meggers
DOI:10.1002/anie.201905647
日期:2019.10.7
catalyzed by a bis-cyclometalated rhodium catalyst in the presence of visible light. Mechanistic experiments and DFT calculations support a mechanism in which a photoexcited catalyst/substrate complex triggers an intramolecular hydrogen-atom transfer followed by a highly stereocontrolled hetero-Diels-Alder reaction. In this reaction scheme, the rhodium catalyst fulfills multiple functions by 1) enabling
An efficient straightforward metal free domino approach was developed for the synthesis of various 8-hydroxy-2,8-dihydroindeno[2,1-c]pyrazoles via [3 + 2] cycloaddition of substituted alkenes and TsDAM (TosylDiAzoMethane). The salient features of this protocol include high efficiency, mild reaction conditions, greener solvent, metal-free reaction, scalability and broad substrate scope along with high
开发了一种有效的直接无金属多米诺骨牌方法,用于通过取代烯烃和 TsDAM(TosylDiAzoMethane)的 [3 + 2] 环加成合成各种 8-羟基-2,8-二氢茚并[2,1- c ]吡唑。该协议的显着特点包括高效、温和的反应条件、更环保的溶剂、无金属反应、可扩展性和广泛的底物范围以及高区域选择性和产量。
Process for modifying rubbers
申请人:NIPPON ZEON CO., LTD.
公开号:EP0087110A1
公开(公告)日:1983-08-31
A process for modifying a rubber, which comprises reacting a rubber having an unsaturated carbon linkage with an organic compound having a carboxyl group and an aldehyde group in the presence of an acid catalyst.