Highly selective divergent cycloaddition reactions of enoldiazo compounds and α‐diazocarboximides catalyzed by copper(I) or dirhodium(II) have been developed. With tetrakis(acetonitrile)copper(I) tetrafluoroborate as the catalyst epoxypyrrolo[1,2‐a]azepine derivatives were prepared in good yields and excellent diastereoselectivities through the first reported [3+3]‐cycloaddition of a carbonyl ylide. Use of Rh2(pfb)4or Rh2(esp)2directs the reactants to regioselective [3+2]‐cycloaddition generating cyclopenta[2,3]pyrrolo[2,1‐b]oxazoles with good yields and excellent diastereoselectivities.
Strain‐Induced Nucleophilic Ring Opening of Donor–Acceptor Cyclopropenes for Synthesis of Monosubstituted Succinic Acid Derivatives
1,2,3‐Trisubstituted donor–acceptor cyclopropenes (DACPs) generated in situ from enoldiazo compounds react with nucleophiles to form α‐substituted succinic acid derivatives in high yields. Initial dirhodium(II) carboxylate catalysis rapidly converts enoldiazo‐acetates or ‐acetamides to DACPs that undergo catalyst‐free Favorskii ring opening with amines, and also with anilines, alcohols, and thiols, when facilitated by catalytic amounts of 4‐dimethylaminopyridine (DMAP). This methodology provides easy access to mixed esters and amides of monosubstituted succinic acids, including derivatives of naturally occurring compounds. It also affords dihydrazide, dihydroxamic acid, and diamide derivatives, as well as α‐substituted tetrahydropyridazine‐3,6‐diones in high yields. Attempts to generate optically enriched DACPs were not successful because their populations having the
- Award ID(s):
- 1763168
- NSF-PAR ID:
- 10237070
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 27
- Issue:
- 1
- ISSN:
- 0947-6539
- Page Range / eLocation ID:
- p. 340-347
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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