jo7b03033_si_003.cif (11.59 kB)

Stereospecific Syntheses of Enaminonitriles and β‑Enaminoesters via Domino Ring-Opening Cyclization (DROC) of Activated Cyclopropanes with Pronucleophilic Malononitriles

Download (11.59 kB)
posted on 17.01.2018, 00:00 by Amrita Saha, Aditya Bhattacharyya, Ranadeep Talukdar, Manas K. Ghorai
Two novel synthetic protocols for the syntheses of highly functionalized five-membered carbocyclic enaminonitriles and β-enaminoesters have been developed via domino ring-opening cyclization (DROC) and DROC/decarboxylative tautomerization of activated cyclopropanes with malononitrile pronucleophiles, respectively. Both of the efficient strategies (yield up to 93%) have been generalized with various donor–acceptor and acceptor cyclopropanes as well as with malononitrile derivatives. The stereospecific variants of the two SN2-type DROC strategies have also been developed by employing enantiopure donor–acceptor (DA) cyclopropanes to synthesize the corresponding nonracemic products with excellent stereoselectivities (dr up to >99:1, ee up to >99%).