1 research outputs found
A Rational Approach to TetraâFunctional PhotoâSwitches
Abstract α,ÏâBis(1,8âdichloroanthracenâ10âyl)alkanes with (CH2)nâlinker units (n=1â4) were synthesized starting from 1,8âdichloroanthracenâ10(9H)âone. This was transformed into anthracenes with allyl, bromomethyl and propargyl substituents in position 10; these were converted in various CâCâbond formation reactions (plus hydrogenation), leading to two anthracene units flexibly linked by α,Ïâalkandiyl groups. 1,2âEthandiylâ and 1,3âpropandiylâlinked derivatives were functionalized with ethynyl groups in positions 1, 8, 1â and 8â, and these terminally functionalized by Me3Sn groups using Me2NSnMe3. All linked bisanthracenes were subjected to UV light induced cyclomerization and a series of 9,10â:â9â,10ââphotoâcyclomers were obtained. Their thermal cycloreversion and (repeated) switchability was demonstrated. 1,3âBis{1,8âbis[(trimethylstannyl)ethynyl]anthracenâ10âyl}propane served as model compound for photoâswitchable acceptor molecules and its open and closed forms were characterized by NMR and DOSY experiments