Bankar Onkar S, Laha Debasish, Meher Kajal B, Bhat Ramakrishna G
Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, NCL Colony, Pashan, Pune, Maharashtra, 411008, India.
Chem Asian J. 2023 Dec 1;18(23):e202300774. doi: 10.1002/asia.202300774. Epub 2023 Nov 9.
Herein, for the first time we have explored the umpolung reactivity of the vinylogous carbon center of diazo arylidene succinimide (DAS) through rhodium catalysis to achieve [2,3]-Stevens rearrangement of α-thioether esters. The protocol has successfully demonstrated the distal C-H bond functionalization of the α-thioether esters. Alongside, the carbenoid reactivity of DAS has also been achieved with Doyle-Kirmse reaction of allyl/propargyl phenyl sulfides. The protocol proved to be practical to synthesize a wide variety of [2,3]-Stevens rearrangement products exclusively and the possible side products emanating from Pummerer rearrangement and [1,2]-Stevens rearrangement were not observed. This catalytic protocol works smoothly in environmentally benign solvent under open air to afford the corresponding desired products with excellent diastereo-, regio- and chemo-selectivities in good to excellent yields. The protocol also proved to be scalable on gram quantity.
在此，我们首次通过铑催化探索了重氮亚芳基琥珀酰亚胺（DAS）的乙烯型碳中心的极性反转反应活性，以实现α-硫醚酯的[2,3]-史蒂文斯重排。该方法成功地证明了α-硫醚酯的远端C-H键官能化。此外，通过烯丙基/炔丙基苯基硫醚的多伊尔-基尔姆塞反应，也实现了DAS的类卡宾反应活性。该方法被证明对于专门合成多种[2,3]-史蒂文斯重排产物是实用的，并且未观察到由普默勒重排和[1,2]-史蒂文斯重排产生的可能副产物。这种催化方法在环境友好的溶剂中于露天条件下顺利进行，以良好至优异的产率提供具有优异非对映选择性、区域选择性和化学选择性的相应所需产物。该方法也被证明可扩大至克级规模。
