Nazarov cationic π-cyclizations were employed in the synthesis of three substituted camphor-derived cyclopentadienyl ligands bearing a 3-methyl, 3-t-butyl or 3-phenyl substituent on the (1R,7S)-1,10,10-trimethyltricyclo[5,2,1,02,6]deca-2,5-diene framework. These ligands were converted to diastereomeric mixtures of bis(cyclopentadienyl)zirconium and -titanium dichlorides. In each case, a C2-symmetrical
Nazarov阳离子π-环化反应用于合成三个在(1R,7S)-1,10,10-三甲基
三环上带有3-甲基,3-叔丁基或3-苯基取代基的
樟脑衍生的
环戊二烯基
配体[ 5,2,1,0 2,6 ] deca-2,5-diene骨架。这些
配体转化为双(
环戊二烯基)
锆和
二氯化钛的非对映异构体混合物。在每种情况下,C 2对称异构体是粗反应产物混合物中的主要异构体,并且除一种情况外,在所有情况下都可以通过结晶获得纯的C 2对称非对映异构体。