Design and Synthesis of Linear and Bow Shaped Ferroelectric Liquid Crystal Isomers Derived From L-Tyrosine
摘要:
A novel series comprising of two distinct ferroelectric liquid crystalline structural isomers, viz.. (S)-1,4-diphenylene bis(2-chloro-3-(4-dodecyloxyphenyl)-propionate) (DCDP-1) and (S)-1.3-diphenylene bis(2-chloro-3-(4-hydroxyphenyl)-propionate) (DCDP-2), have been synthesized and characterized by thermal microscopy (TM), differential scanning calorimetry (DSC). spontaneous polarisation (PS) and response times (T). The preliminary studies on thermal and ferroelectric properties reveal that the isomers show altogether a different trend of thermal and phase behaviour. The thermal analyses (TM and DSC) suggest the existence of different phase variants. Further, the ferroelectric studies infer a different chiral behavior among DCDP-1 and DCDP-2 compounds wherein DCDP-2 showed a wide ferroelectric thermal range with high magnitudes of P-S (three fold) and response rimes (two fold).
Processes for conversion of tyrosine to p-hydroxystyrene and p-acetoxystyrene
申请人:Shuey W. Steven
公开号:US20070213569A1
公开(公告)日:2007-09-13
Tyrosine was converted to p-hydroxystyrene in a two-step reaction without purification of individual intermediates. Conditions were determined for bromination of tyrosine in which reactive intermediates were formed. The mixture of these intermediates was used directly in a second step reaction to produce p-hydroxystyrene. The p-hydroxystyrene was further acetylated to produce p-acetoxystyrene in the second step reaction vessel.
METHODS FOR CONVERSION OF TYROSINE TO P-HYDROXYSTYRENE AND P-HYDROXYCINNAMIC ACID
申请人:SHUEY STEVEN W.
公开号:US20080167493A1
公开(公告)日:2008-07-10
Three different reaction steps were combined to provide methods for preparing p-hydroxystyrene and p-hydroxycinnamic acid monomers from tyrosine. The three steps include reductive alkylation of tyrosine, followed by oxidation to the N-oxide, and thermal Cope elimination. During Cope elimination, either p-hydroxycinnamic acid or p-hydroxystyrene was produced depending on the absence or presence of base, respectively. Additionally, p-acetoxystyrene may be prepared by reacting the prepared p-hydroxystyrene either directly or after isolation with an acetylating agent.
PROCESSES FOR CONVERSION OF TYROSINE TO P-HYDROXYSTYRENE AND P-ACETOXYSTYRENE
申请人:E.I. DU PONT DE NEMOURS AND COMPANY
公开号:EP1999095A2
公开(公告)日:2008-12-10
US7402713B2
申请人:——
公开号:US7402713B2
公开(公告)日:2008-07-22
[EN] PROCESSES FOR CONVERSION OF TYROSINE TO P-HYDROXYSTYRENE AND P-ACETOXYSTYRENE<br/>[FR] PROCEDES DE CONVERSION DE LA TYROSINE EN P-HYDROXYSTYRENE ET P-ACETOXYSTYRENE
申请人:DU PONT
公开号:WO2007103478A2
公开(公告)日:2007-09-13
[EN] Tyrosine was converted to p-hydroxystyrene in a two-step reaction without purification of individual intermediates. Conditions were determined for bromination of tyrosine in which reactive intermediates were formed. The mixture of these intermediates was used directly in a second step reaction to produce p-hydroxystyrene. The p-hydroxystyrene was further acetylated to produce p-acetoxystyrene in the second step reaction vessel. [FR] La présente invention concerne une tyrosine qui a été convertie en p-hydroxystyrène au cours d'une réaction en deux étapes sans purification des divers intermédiaires. Des conditions ont été déterminées pour la bromination de la tyrosine dans laquelle des intermédiaires réactifs ont été formés. Le mélange de ces intermédiaires a été utilisé directement au cours d'une seconde étape de réaction pour produire du p-hydroxystyrène. Le p-hydroxystyrène a en outre été acétylé en vue de produire du p-acétoxystyrène dans la cuve à réaction de la seconde étape.