Racemic and Optically Pure Heptahelicene-2-carboxylic Acid: Its Synthesis and Self-Assembly into Nanowire-Like Aggregates
作者:Jiří Rybáček、Gloria Huerta-Angeles、Adrian Kollárovič、Irena G. Stará、Ivo Starý、Philipp Rahe、Markus Nimmrich、Angelika Kühnle
DOI:10.1002/ejoc.201001110
日期:2011.2
methoxycarbonylation reaction to provide, after hydrolysis, heptahelicene-2-carboxylic acid. The racemate was resolved into enantiomers by semipreparative HPLC on a chiral column. The helicity of (+)-(P)-heptahelicene-2-carboxylic acid was assigned by correlating its CD spectrum to that of the known (+)-(P)-heptahelicene. Racemic heptahelicene-2-carboxylic acid was deposited on calcite (10-14) to undergo self-assembly
Heptahelicene-2-羧酸是由适当官能化的萘结构单元有效合成的。甲氧基取代的 1,1'-乙炔-1,2-二基双(2-but-3-yn-1-ylnaphthalene)在 CpCo(CO)(2)/PPh(3) 存在下环化为 2-甲氧基-7,8,11,12-四氢庚烷,其被转化为庚烷-2-基三氟甲磺酸酯。该反应性中间体经过 Pd(OAc)(2)/dppp 催化的甲氧基羰基化反应,在水解后提供七烯-2-羧酸。通过手性柱上的半制备型 HPLC 将外消旋体拆分为对映异构体。(+)-(P)-heptahelicene-2-羧酸的螺旋度是通过将其 CD 光谱与已知的 (+)-(P)-heptahelicene 相关联来指定的。