Facile Synthesis of Thioamides via P2S5-Mediated Beckmann Rearrangement of Oximes
作者:Jiangsheng Li、Chao Cheng、Xinrui Zhang、Zhiwei Li、Feifei Cai、Yuan Xue、Weidong Liu
DOI:10.1002/cjoc.201200448
日期:2012.8
A facile and efficient approach to the synthesis of secondary thioamides from ketoximes via Beckmannrearrangement has been established, using phosphorus pentasulfide as a dehydrating and thiating agent. It is also efficient for the preparation of primary thiobenzamide from benzaldoxime. This approach features simple‐operation, easy‐control and good to excellent yields.
Method for preparing lactams having 8 to 15 carbon atoms from the
申请人:Huls Aktiengesellschaft
公开号:US04689412A1
公开(公告)日:1987-08-25
The present invention is a process for preparing lactams having 8 to 15 carbon atoms by the Beckmann rearrangement of the corresponding oximes in a solution of an organic solvent by means of 0.5 to 10% by weight referred to the oxime of an acid derivative acting as a catalyst. The anhydrides of organic sulfonic acids or of sulfuric acid half esters or mixed anhydrides of organic sulfonic acid and anhydrides of sulfuric acid half esters are used as the catalysts.
The present invention relates to a method for producing a high purity, high quality amide compound, particularly, lactam. A first embodiment of the present invention is characterized in that an amount of each of a halide, an aldehyde compound, an alcohol compound and a nitrile compound contained in a solution recycled into an oxime-forming step is controlled to an amount of 0.4 mol % or less based on the ketone as a starting material. A second embodiment of the present invention is characterized in that one or more compounds selected from the group consisting of a ketone, an oxime and an amide compound are purified by hydrogenation and/or crystallization for eliminating impurities containing a double bond. A third embodiment of the present invention is characterized in that a content of impurities having a cyclic bridge structure is controlled by using a cycloalkanone purified by recrystallization.
Disclosed is a method for industrially efficiently producing a lactam compound having 8 to 15 carbon atoms at low cost by allowing a rearrangement reaction of a cyclic oxime compound to proceed without causing large amounts of by-products such as ammonium sulfate.
[Solving Means] Disclosed is a method for producing a lactam compound, which includes the step of rearranging a cyclic oxime compound in a nonpolar solvent B in the presence of an aromatic compound A to give the lactam compound, in which the aromatic compound A has a leaving group bonded to a carbon atom constituting its aromatic ring and contains, as an atom constituting the aromatic ring, a heteroatom, or a carbon atom bonded with an electron-withdrawing group, the cyclic oxime compound is represented by following Formula (1):
wherein “m” denotes an integer of 7 to 14,
and the lactam compound is represented by following Formula (2):
wherein “m” is as defined above.
Zur Kenntnis des Kohlenstoffringes. 53. Mitteilung. 3,4-Dimethyl-2,6-polymethylen-phenole
作者:V. Prelog、P. Barman、M. Zimmermann
DOI:10.1002/hlca.19500330219
日期:——
Durch Kondensation von Cyclanon-(2)-carbonsäure-(1)-estern mit der quaternären Base aus 1,1-Bis-(diäthylamino-methyl)-aceton wurden ungesättigte δ-Diketo-carbonsäure-ester IV mit 6, 7, 8, 9 und 13gliedrigem Ring erhalten. Diese cyclisierte man mit Salzsäure in Eisessig, wobei sich aus den 6 und 7 gliedrigen monocyclischen Ausgangsprodukten 3,4-Polymethylen-phenole VI, aus denjenigen mit 8. 9 und 13