Patent GB-906523-A (GB)
Title: Compounds of the 1,4-divinylbenzene series and their production
Inventor: STILZ WALTER
IPC: C07D317/54
Filed: 1960-05-13
Abstract: Compounds of the 1,4-divinylbenzene series such as 1,4-distyrylbenzene, 1,4-bis-(cyanostyryl)-benzenes, 1,4-bis-(dialkoxystyryl)-benzenes, 1,4-bis-styryl-2,5-dialkoxybenzenes, and 1,4-bis-styryl-2,5-dichlorobenzene, are made by reacting a mono- or di-aldehyde, which may have cyano, alkoxy, nitro, dialkylamino, chloro, or alkoxycarbonyl substituents, with a xylylene, diphosphonate or diphosphinate of the formula <FORM:0906523/IV (b)/1> wherein R1 is a hydrocarbon, alkoxy, or aryloxy group, and R2 is hydrocarbon group, R3, R4, R5 and R6 are hydrogen or halogen atoms or alkyl, alkoxy, sulphonic acid nitro, or mercapto groups, or taken in pairs they may represent a carbocyclic ring or a dioxymethylene chain, and R7 and R8 are hydrogen atoms or cyano or carboalkoxy groups in the presence of a proton acceptor such as a hydroxide, alcoholate or amide or an alkali or alkaline-earth metal.  In Example 1, benzaldehyde is mixed with a solution of p-xylylene-tetraethyl phosphonate in dimethylformamide; and then, while stirring vigorously, a methanolic solution of sodium methylate is added. 1,4-Distyrylbenzene is precipitated as yellowish fluorescent leaflets.  Example 20 relates to the preparation of distyrylbenzene by reacting benzaldehyde with the ethyl ester of p - xylylene - bis - phenylphosphinic acid. Examples 5, 15, 22 and 28 relate to the preparation of the following hydrocarbons:-1,4 - dinaphthostyryl-benzene, 1,4-bis-(omega-phenyl-butadienyl)-benzene and 1,4-bis-(p-phenyl-styryl)-benzene.  Example 7 describes the preparation of 1,4-bis-(m-cyanostyryl)-benzene by reacting m-cyanobenzaldehyde with p - xylylene - tetraethyl diphosphonate. Examples 16 and 24 relate to the preparation of the corresponding para- and ortho-cyano compounds.  Example 8 describes the preparation of 1,4-distyryl-2,5-dimethoxybenzene by reacting benzaldehyde with 2,5-dimethoxy-1,4-xylylene-tetraethyl diphosphonate.  Example 12 describes the preparation of 1,4-bis-(21,41-dimethoxystyryl)-benzene. In Example 11, vanillin-tetrahydrofuranyl ether is reacted with p-xylylene-tetraethyl diphosphonate to give 1,4 - bis - (41 - alpha - tetrahydrofuranyloxy - 31 - methoxy-styryl)-benzene, and the latter is then treated with boiling glacial acetic acid whereby 1,4 - bis - (31 - methoxy - 41 - hydroxystyryl)-benzene is obtained. Examples 6 and 19 relate to the preparation of 1,4-bis-(31,41-dioxymethylene-styryl)-benzene. Examples 2, 3, 4, 10, and 17 relate to the preparation of 1,4-bis-(beta-anthraquinonyl-styryl) - benzene, 1,4 - bis - (p-nitrostyryl)-benzene, 1,4-bis-(p-dimethylaminostyryl)-benzene, 1,4-distyryl-2,5-dichlorobenzene and 1,4 - bis - (p-carbmethoxy-styryl)-benzene.  Example 26 describes the reaction of p-xylylene-tetraethyl diphosphonate with 4-formyl-benzoic acid morpholide to yield 1,4-bis-(p-carbmorpholido-styryl)-benzene.  The required xylylene diphosphonates or diphosphinates are made by reacting p-xylylene dichloride, or a nuclear substituted derivative thereof, with a trialkyl phosphite (see Examples 1, 8, 10, 21 and 23) or with phenyl diethoxy phosphine (Example 19).  The 1,4-divinylbenzene compounds have use as optical brighteners.