A pyridine based 1,2-diamine containing only one stereogenic center has been identified for fast aldol reactions (16–48 h). Using 2–5 mol% of (R)- or (S)-PicAm-2, cyclohexanone (3.3 equiv) readily undergoes aldol reactions with o-, m-, and p-substituted aromatic aldehyde partners (limiting reagent), including the poor electrophile 4-methylbenzaldehyde (95–99% ee). Furthermore, functionalized cyclic
一种
吡啶 基于 1,2-二胺已确定仅包含一个立体定向中心可进行快速的羟醛反应(16-48小时)。使用2–5 mol%的(R)-或(S)-PicAm- 2,
环己酮(3.3当量)容易经历与羟醛缩合反应ö - ,米- ,和p取代的芳族醛伙伴(限定试剂),包括较差的亲电4-甲基
苯甲醛(95-99%ee)。此外,迄今为止,功能化的环状酮底物已使用最低的催化剂负载量(5.0 mol%)以最高的收率和对映选择性转化为四种羟醛产物9-12。