Enantioselective Synthesis of Axially Chiral Styrene‐Carboxylic Esters by Rhodium‐Catalyzed Chelation‐Controlled [2+2+2] Cycloaddition
Enantioselective Synthesis of Axially Chiral Styrene‐Carboxylic Esters by Rhodium‐Catalyzed Chelation‐Controlled [2+2+2] Cycloaddition
复制标题
铑催化螯合控制的[2+2+2]环加成对映选择性合成轴向手性苯乙烯-羧酸酯
DOI：
10.1002/anie.202202542
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Tanaka Ken
中科院分区：
文献类型：
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作者：
Yokose Daisuke;Nagashima Yuki;Kinoshita Suzuka;Nogami Juntaro;Tanaka Ken
采用阳离子铑(I)/H8 - BINAP配合物催化1,6 -和1,7 -二炔与1,3 -炔-羧酸酯的螯合控制[2+2+2]环加成反应，以高收率、高对映选择性地合成了轴手性苯乙烯-羧酸酯。2对称轴向手性顺式和反式二苯乙烯二羧酸酯的非映对和对映选择性合成也分别通过1,2 - 2+2+2两个分子的1,6 -二炔与2,3 -马来酸二炔基和2,3 -富马酸二炔基的双环加成反应实现。在这些反应中，与铑配位的五元螯合物1,3 -炔羧酸酯比与铑配位的六元螯合物反应性更强，尽管这两种螯合方式都具有出色的对映选择性。通过DFT计算阐明了阳离子铑(I)催化螯合控制的[2+2+2]环加成的对映体选择机制。
Axially chiral styrene‐carboxylic esters were synthesized in high yields with excellent enantioselectivity by the cationic rhodium(I)/H8‐BINAP complex‐catalyzed chelation‐controlled [2+2+2] cycloaddition reactions of 1,6‐ and 1,7‐diynes with 1,3‐enyne‐carboxylic esters. The diastereo‐ and enantioselective synthesis ofC2symmetric axially chiralcisandtrans‐stilbene‐dicarboxylic esters was also achieved by the double [2+2+2] cycloaddition reactions of two molecules of the 1,6‐diyne with 2,3‐dialkynylmaleate and 2,3‐dialkynylfumarate, respectively. In these reactions, the 1,3‐enyne‐carboxylic esters coordinating to rhodium with a five‐membered chelate were more reactive than those coordinating to rhodium with a six‐membered chelate, although both chelation modes realized excellent enantioselectivity. The enantioselection mechanism of the cationic rhodium(I)‐catalyzed chelation‐controlled [2+2+2] cycloaddition was elucidated by DFT calculations.