Liquid crystalline mixtures containing compounds of the formula ##STR1## wherein n stands for the number 0 or 1; X.sup.1 and X.sup.2 denote single covalent bonds or one of the symbols X.sup.1 and X.sup.2 also denotes --COO--, --OOC-- or --CH.sub.2 CH.sub.2 --; the rings A.sup.1, A.sup.2 and A.sup.3 represent 1,4-phenylene, 2-fluoro-1,4-phenylene or trans-1,4-cyclohexylene or one of these rings also represents a 2,5-disubstituted pyrimidine ring or a trans-2,5-disubstituted m-dioxane ring; R.sup.1 signifies 4-alkenyl or on a cyclohexyl ring also 2Z-alkenyl; and R.sup.2 denotes alkyl, alkoxy, --CN or --NCS, as well as the manufacture of these compounds and the use for electro-optical purposes are described.
Cross‐Si‐ing the Jordan: Cross‐coupling reactions of 2‐(2‐hydroxyprop‐2‐yl)phenyl‐substituted alkylsilanes with a variety of aryl halides proceed in the presence of palladium and copper catalysts. The use of K3PO4 base allows for highly chemoselective alkyl coupling with both primary and secondary alkyl groups (Alk).
乔丹的交叉反应:2-(2-羟基丙-2-基)苯基取代的烷基硅烷与各种芳基卤化物的交叉偶联反应在钯和铜催化剂的存在下进行。K 3 PO 4碱的使用允许与伯烷基和仲烷基(Alk)都高度化学选择性的烷基偶联。
Synthesis ofrac-ar-Curcumen-15-al
作者:Peter Weyerstahl、Volker Schlicht
DOI:10.1002/jlac.199719970125
日期:1997.1
AbstractStarting from p‐tolunitrile (4) via alkylation with the bromoacetal 12 (→ 8), and with MeI (→ 9), hydrolysis to 10, Wittig reaction (→ 7) and DIBAH reduction, the rac‐ar‐curcumen‐15‐al (2) was obtained. The cumin‐like, citrus odor of rac‐2 is similar to that of the isolated (−)‐2.