Seminar: Donor-Acceptor Cyclopropanes: Unique Structural Units to Access Carbo- and Heterocyclic Compounds

Thursday, 21 February 2019 - 12:00pm – Thursday, 21 February 2019 - 1:00pm  |  ChemSci M17

Speaker: Prof Daniel Werz

Donor-acceptor (DA) cyclopropanes are highly strained entities which are unique building blocks for heterocyclic and carbocyclic systems.[1,2] Our previous work was mainly focused on rearrangement reactions of DA cyclopropanes leading to spiroketals, oligoacetals,[3] pyrrols[4] and thiophenes The recent developments in the lab deal with [3+n]-cycloaddition (n = 1, 2, 3, 4) and ring-opening reactions of these three-membered rings systems.[5]

Approaches to four-membered ring formation by insertion of one atom are presented. The formation of five-membered rings with unusual 2-atom moieties being inserted are discussed[6] or by dual Lewis acid and redox catalysis converting an electrophile in situ into a nucleophile.[7] [3+3]-Cycloaddition reactions using carbonyl ylides allow the preparation of complex bicyclic scaffolds in a simple manner. 1,3-Bisfunctionalization studies pave the way to 1,4-bisamines by the formal addition of “NHR” and “CH2NHR” to the 1- and 3-position of the cyclopropane.[8] 

[1] H.-U. Reißig, R. Zimmer, Chem. Rev. 2003, 103, 1151-1196.
[2] D. B. Werz, J. Kaschel, D. B. Werz, Angew. Chem. Int. Ed. 2014, 53, 5504-5523. 
[3] T. F. Schneider, J. Kaschel, S. I. Awan, B. Dittrich, D. B. Werz, Chem. Eur. J. 2010, 16, 11276-11288.
[4] J. Kaschel, T. F. Schneider, D. Kratzert, D. Stalke, D. B. Werz, Angew. Chem. Int. Ed. 2012, 51, 11153- 11156.
[5] a) L. K. B. Garve, M. Pawliczek, J. Wallbaum, P. G. Jones, D. B. Werz, Chem. Eur. J. 2016, 22, 521-525. b) L. K. B. Garve, M. Petzold, P. G. Jones, D. B. Werz, Org. Lett. 2016, 18, 564-567. c) J. Wallbaum, L. K. B. Garve, P. G. Jones, D. B. Werz, Org. Lett. 2017, 19, 98-101.
[6] A. U. Augustin, M. Sensse, P. G. Jones, D. B. Werz, Angew. Chem. Int. Ed. 2017, 56, 14293-14296.
[7] A. Lücht, L. J. Patalag, A. U. Augustin, P. G. Jones, D. B. Werz, Angew. Chem. Int. Ed. 2017, 56, 10587- 10591.
[8] L. K. B. Garve, P. G. Jones, D. B. Werz, Angew. Chem. Int. Ed. 2017, 56, 9226-9230.