Synthesis of 2,2,5,5-Tetrasubstituted 1,4-Dioxa-2,5-disilacyclohexanes via Organotin(IV)-Catalyzed Transesterification of (Acetoxymethyl)alkoxysilanes
作者:Sascha A. Erhardt、Florian Hoffmann、Jürgen O. Daiß、Jürgen Stohrer、Eberhardt Herdtweck、Bernhard Rieger
DOI:10.1002/chem.201202124
日期:2013.4.8
5‐disilacyclohexanes 3, 8 a–c, and 11 a–c if treated with organotin(IV) catalysts such as dioctyltin oxide. The reaction proceeds through transesterification of the acetoxy and alkoxy units followed by ring‐closure to form a dimeric six‐membered ring. The corresponding alkyl acetates are formed as the reaction by‐products. With these mild conditions, the method overcomes the drawbacks of previously reported
(乙酰氧基)硅烷2,7 - ç,和10 - ç具有至少一个烷氧基的通式,(AcOCH 2)的Si(OR)3- Ñ(CH 3)Ñ(R:ME等,我镨; ñ = 0,1,2),由相应的(氯甲基)硅烷的合成1,6 - ç,和9 - ç相转移催化的条件下通过用乙酸钾。发现这些化合物可提供2,2,5,5-有机取代的1,4-二氧杂-2-2,5-二硅环己烷3,8 - ç,和11 - ç如果与有机锡(IV)处理的催化剂,例如二辛基氧化锡。反应通过乙酰氧基和烷氧基单元的酯交换反应进行,然后闭环形成二聚六元环。相应的乙酸烷基酯作为反应副产物形成。在这些温和条件下,该方法克服了以前报道的合成路线的缺点,可提供2,2,5,5-四甲基-1,4-二氧杂-2-2,5-二硅环己烷(3),甚至可以以高收率和高纯度合成在硅原子上带有水解不稳定的烷氧基取代基的1,4-二氧杂-2-2,5-二硅环己烷。这些新材料已通过NMR光谱,元素分析,质谱和X射线分析(trans