1,10-, 1,4-, and 1,2-Eliminations and 1,5- and 1,7-rearrangements in the reactions of substituted 9-anisylidene-9,10-dihydroanthracenes and anthrones in acetic acid

Calix[4]arenes with Two Different Chemical Modifications at the Bridges

“…A possible explanation for the formation of 23a and 23b is that, since the reaction of the calixarene carbocation with the crowded mesitylene is slow, a demethylation reaction can successfully compete with the Fridel–Crafts alkylation. It may be possible also that the demethylation reaction occurs at a carbocation intermediate and that the O-Me cleavage is facilitated on a ring involved in delocalization of the positive charge, which may rationalize why the ring selectively demethylated in the product is the one located between the two substituted bridges.…”

Photoreactivity of some .alpha.-arylvinyl bromides in acetic acid. Selectivity toward bromide versus acetate ions as a mechanistic probe

“…The vinyl bromides la-ld and 2 were available from a previous study.17 The syntheses and spectral data of these compounds have been reported: 1 -bromo-1,2,2-tris(p-methoxyphenyl)ethene (la),54,55 (£/Z)-1 -bromo-1,2-bis(p-methoxyphenyl)-2phenylethene (lb,c),53 1 -bromo-l-(p-methoxyphenyl)-2,2-diphenylethene (Id),55 and 9-(a-bromop-methoxybenzylidene)anthrone (2). 56 The vinyl bromides le-lg were synthesized according to literature procedures via bromination and dehydrobromination of the corresponding ethylene compounds: 1 -bromo-2,2-bis(p-methoxyphenyl)-1 -phenylethene (le)l,b•57 and (£/Z)-l-bromo-2-(p-methoxyphenyl)-l,2-diphenylethene (lf,g).19b•58 The preparation of [82Br]Et4NBr by neutron irradiation of Et4NBr has already been reported.17 The irradiations were performed at the Interfaculty Reactor Institute in Delft, The Netherlands. Identification of Products.…”

A facile synthesis of 10-arylmethylene anthracenones under microwave irradiation

“…They have been employed for synthesis of 9-(α-bromoarylmethylene) anthracenone and its derivatives. [1][2][3][4][5] Derivatives of some arylmethylene anthracenones, such as 10-(4-acetamidobenzylidene)-9(10H)anthracenone (DK-V-47), 10-aminomethylene-1,8-dihydroxy-9(10H) anthracenone and 10-benzoyl-1,8-dihydroxy-9(10H) anthracenone etc. possess biological activity.…”

“…[6][7][8] In general, 10-arylmethylene anthracenones were synthesised by the condensation of aromatic aldehyde with anthracenone using piperidine as catalyst in ethanol, acetic anhydride, pyridine or xylene. [1][2][3][9][10] Tewari and Gupta 11 reported that 10-arylmethylene anthracenones were synthesised by reaction of aromatic aldehydes with the ylide of the 10-anthracenonyl triphenyl phosphonium or arsonium salt. Very recently, we 12 have reported that 10-arylmethylene anthracenones were obtained by the condensation of aromatic aldehydes with anthracenone using bis-(p-methoxyphenyl)telluroxide (BMPTO) as catalyst in DMSO.…”