Organocatalytic Stereoisomerization versus Alkene Isomerization: Catalytic Asymmetric Synthesis of 1-Hydroxy-trans-2,5-diphenylphospholane 1-Oxide
作者:Lukas Hintermann、Marco Schmitz、Oleg Maltsev、Panče Naumov
DOI:10.1055/s-0032-1316835
日期:——
total synthesis of Fiaud’s acid, which is a building block for chiral phospholane synthesis, has been realized in five steps from thiophene, using nickel-catalyzed Wenkert arylation, McCormack cycloaddition, asymmetric dihydro-1H-phosphole isomerization, hydrolysis, and diastereoselective hydrogenation. The potential for an organocatalytic asymmetric stereoisomerization or alkene isomerization as atom-economic
摘要 研究了具有最小结构变化的有机催化不对称立体异构化或烯烃异构化作为原子经济反应的潜力。1,4- diarylbuta-1,3-二烯与(二烷基氨基)dichlorophosphane和三氯化铝麦科马克环加成给出的内消旋-2,5-二芳基-1-(二烷基氨基)-1-氧代-2,5-二氢- 1 ħ -磷脂,被确定为不对称异构化成(1 R,5 R)-2,5-二芳基-1-(二烷基氨基)-1-氧代-4,5-二氢-1 H的合适底物双功能有机催化剂(金鸡纳生物碱,竹本催化剂)存在下的2-膦,ee最高定量可达91%。研究了底物范围和催化机理。该反应涉及质子被碱基提取,但不存在初级氘KIE。将富集的(1 R,5 R)-1-(二乙基氨基)-1-氧代-2,5-二苯基-4,5-二氢-1 H-磷酰基水解为(5 R)-1-羟基-1-氧代。 -2,5-二苯基-4,5-二氢-1 H-磷脂,在溶解的金属条件下非对映选择性地氢化,得到(2