New Synthesis of β-diazocarbonyl compounds enables discovery of a rare intra-molecular Rh-catalyzed carbene C-H insertion
The development of methodologies for the synthesis of α-diazocarbonyl compounds has captured the imagination of chemists for more than hundred years [1]. However, methods that provide access to β-diazocarbonyl derivatives are scarce [2]. Herein, we present a general methodology for the synthesis of β-diazocarbonyl compounds by using a broad range of ketone silyl enol ethers and hypervalent iodine reagents as electrophilic diazo transfer reagents [3]. The process is scalable, works at room temperature and has wide functional group tolerance represented in more than 40 examples. The value of these compounds has been exploited in the discovery of a new catalytic cyclopropane synthesis. This process involves a rare intra-molecular Rh-catalyzed carbene C-H insertion process that occurs with excellent regio- and diastereoselectivity.
References
[1] (a) A. Ford, H. Miel, A. Ring, C. N. Slattery, A. R. Maguire, M. A. McKervey, Chem. Rev. 2015, 115, 9981-10080 (b) G.Maas, Angew. Chem. Int. Ed. 2009, 48, 8186-8195.
[2] J. Barluenga, G. Lonzi, L. Riesgo, M. Tomas, L. A. Lopez, J. Am. Chem. Soc. 2011, 133, 18138-18141.
[3] (a) R.Weis, J. Seubert, F. Hampel, Angew. Chem. Int. Ed. Engl.1994, 33, 1952-1953 (b) C. Schnaars, M. Hennum, T. Bonge-Hansen, J. Org. Chem.2013, 78, 7488-7497. (c) Z. Wang, A. G. Herraiz, A. M. del Hoyo, M. G. Suero,Nature.2018, 554, 86-91.
