the allomorphism of a photochromic diarylethene

《the allomorphism of a photochromic diarylethene》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、TETRAHEDRONLETTERSPergamonTetrahedronLetters44(2003)10111014Theallomorphismofaphotochromicdiaryletheneaa,aaabShou-ZhiPu,Fu-ShiZhang,*FanSun,Ru-JiWang,Xin-HongZhouandShek-KiuChanaDepartmentofChemistry,TsinghuaUniversity,Beijing100084,ChinabFacultyofScienceandTechnology,UniversityofMacau

2、,Macau3001,ChinaReceived14October2002;revised21November2002;accepted29November2002Abstract—Thephotochromicdiarylethene,1,2-bis(2-methyl-5-(2,2
-dicyanovinyl)-thien-3-yl)perfluorocyclopentene(1a),wassyn-thesizedbyanovelmethod.Twokindsofsinglecrystalsofthecompoundwereobtaineddependingonth

3、edifferentrecrystallizationconditionsandtheirstructuresweredeterminedbyX-raycrystallographicanalysis.Allomorphismofthephotochromicdiarylethenewasdiscovered.Thecompoundunderwentaphotochromicreactionbothinsolutionandinthesinglecrystallinephaseoftheanti-parallelconformer.©2003ElsevierScie

4、nceLtd.Allrightsreserved.Muchattentionhasbeendevotedtophotochromicanycrystallinephaseisdeterminedbythecrystalliza-compoundsbecauseoftheirpotentialapplicabilitytotionconditions,suchastherecrystallizationsolvent,1opticalmemoriesandphotonicswitchingdevices.concentration,temperature,thevel

5、ocityofcrystalliza-Diaryletheneswithheterocyclicarylgroupsaremosttion,andsoon.Inthisletter,itisourgoaltoreportpromisingcompoundsforsuchapplicationsduetotheallomorphismofthephotochromiccompound1,2-bis-goodthermalstabilityofbothisomersandtheirhigh(2-methyl-5-(2,2
-dicyanovinyl)-thien-3-y

6、l)perfluoro-27fatigueresistanceandrapidresponsetime.cyclopentene(1a),synthesizedinveryhighyieldbyanovelmethod.TwotypesofcrystalsofthecompoundAlthoughmanyphotochromiccompoundshavebeenwereobtainedbycontrollingdifferentrecrystallizationreportedsofar,compoundswhichshowstrongpho-conditions.U

7、singtheX-raycrystallographicanalysistochromicreactivityinthecrystallinephaseareverymethod,wefoundthatallmoleculesofthecompoundrare.2,8Generally,diaryletheneshaveinterconvertingarepackedeitherinanactiveanti-parallelconforma-parallelandanti-parallelconformationsinsolution,intion(1a-
)o