α′,α′‐tetraphenyl‐1,3‐dioxolan‐4,5‐dimethanamines) (Scheme 2) and ureas, 12–15, and to TADDOP derivatives with seven‐membered OPO ester rings (Schemes 3 and 4). Cl/P‐Replacement via the MichaelisArbuzov reaction (Scheme 7) on mono‐ and dichlorides, derived from TADDOL, are described. It was not possible to obtain phosphines with the P‐atom attached to the benzhydrylic C‐atom of the TADDOL skeleton
TADDOL(= α,α,α' ,α' -Tetraaryl -1,3-二氧戊环-4,5-二甲醇)和相应的二氯化物被转化成TADDAMINs(=(4小号,5小号)-2,2,Ñ,N'-四甲基-α,α,α',α'-四苯基-1,3-二氧杂戊基4,5-二甲胺(方案2)和脲12至15以及具有七元O的TADDOP衍生物 P 0酯环(方案3和4)。Cl / P-替换通过的米氏阿尔布佐夫反应(方案7上的单-和二氯化物),从TADDOL衍生,进行说明。无法获得P原子连接到TADDOL骨架的二羟基C原子上的膦(方案6和7)。讨论了30多种新的TADDOL衍生物中的10种的X射线晶体结构(图1和2)。提供了完整的实验细节。
Ni-Catalyzed Asymmetric Cycloisomerization of Dienes by Using TADDOL Phosphoramidites
3‐dioxolane‐4,5‐dimethanol (TADDOL)‐based phosphoramidites has been synthesized and applied in the Ni‐catalyzed cycloisomerization of different dienes. Through the systematic variation of the three structural motifs of the lead structure, that is, the amine moiety, the protecting group, and the aryl substituents, the ligand features could be optimized for the asymmetriccycloisomerization of the model substrate
合成了基于α,α,α,α-四芳基-1,3-二氧戊环-4,5-二甲醇(TADDOL)的亚磷酰胺库,并将其用于Ni催化的不同二烯的环异构化。通过铅结构的三个结构基序(即胺部分,保护基和芳基取代基)的系统变化,可以优化配体特征,以使模型底物二烯丙基丙二酸二乙酯的不对称环异构化。新催化体系的底物范围已扩展到其他二烯丙基底物,包括不对称二烯。总体上具有高达13 500 h -1的极高活性,对五元外亚甲基亚环戊烷的选择性很高,对映选择性高达92% ee 已经实现。