申请人:Eastman Kodak Company
公开号:US04720559A1
公开(公告)日:1988-01-19
There are disclosed novel benzofurans having the following structural formula: ##STR1## wherein R is alkenyl of 1 to 6 carbon atoms or aryl of from 6 to 10 carbon atoms; R.sub.1 is H, alkali metal, or alkyl of 1 to 4 carbon atoms; and R.sub.2 is alkyl or alkoxy of from 1 to 5 carbon atoms, hydrogen, amino or dialkylamino, nitro, sulfonyl, alkyl or aryl thioether or halide. Also disclosed is a novel process of making the benzofurans, comprising the step of cyclizing an o-(2-carboxyvinyl)phenyl unsaturated alkyl ether in the presence of a base selected from the group consisting of KOH, NaOH, LiOH, dimsyl sodium, lithium diisopropylamide, potassium tert-butoxide, and mixtures thereof, at room temperature.
揭示了一种具有以下结构式的新型苯并呋喃:##STR1##其中,R是1至6个碳原子的烯基或6至10个碳原子的芳基;R.sub.1是H,碱金属或1至4个碳原子的烷基;R.sub.2是1至5个碳原子的烷基或烷氧基,氢,氨基或二烷基氨基,硝基,磺酰基,烷基或芳基硫醚或卤素。还揭示了一种新的制备苯并呋喃的方法,包括在存在以下基团的碱的情况下,将o-(2-羧基乙烯基)苯基不饱和烷基醚环化,所述基团选择自KOH,NaOH,LiOH,二甲基亚砜钠,二异丙基胺锂,叔丁氧基钾和其混合物,在室温下进行。