A convenient resolution method for 1,1′-bi-2-naphthol and 4,4′-dibromo-1,1′-spirobiindane-7,7′-diol with menthyl chloroformate in the presence of TBAB
作者:Zhian Li、Xinmiao Liang、Fan Wu、Boshun Wan
DOI:10.1016/j.tetasy.2003.12.041
日期:2004.2
A convenient resolution method for 1,1′-bi-2-naphthol and 4,4′-dibromo-1,1′-spirobiindane-7,7′-diol has been developed with crude (−)-menthyl chloroformate as the resolution reagent in the presence of tetrabutylammonium bromide acting as a phase transfer catalyst in an aqueous NaOH/CH2Cl2 two phase solution. The deprotection of the hydroxy group was carried out via an aqueous KOH/EtOH solution. Both
以粗制(-)-薄荷基氯甲酸酯为拆分剂,开发了一种简便的拆分方法,用于1,1'-联-2-萘酚和4,4'-dibromo-1,1'-螺双茚满-7,7'-二醇在四丁基溴化铵的存在下,在NaOH / CH 2 Cl 2水溶液中作为相转移催化剂使用该试剂。羟基的脱保护通过KOH / EtOH水溶液进行。高产率地获得了1,1'-联-2-萘酚和4,4'-二溴-1,1'-螺双茚满-7,7'-二醇的两种对映体。(S)-(+)和(R)-(-)-4,4'-二溴-1,1'-螺双茚满-7,7'-二醇高于99%。大部分(-)-薄荷醇可以很容易地在脱保护步骤中回收,因此无需进一步纯化即可重新用于形成(-)-薄荷基氯甲酸酯。