Nazmiye Yapici - Darzens Reaction of Acyl Phosphonates with α-Bromo Ketones: Selective Synthesis of cis- and trans-Epoxyphosphonates

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      Publication Details (including relevant citation   information):

      Ayhan S. Demir, Mustafa Emrullahoglu, Eser Prikin, Nazmiye Akca,   J. Org. Chem.,2008,    73   (22), pp 8992–8997, DOI:10.1021/jo801818p

      Abstract:

        Acyl phosphonates with α-halo ketones in the presence of bases at   room temperature affordcis-   and   trans-epoxyphosphonates   in good chemical yields and high selectivities using different   bases. The diastereoselectivity of this reaction is easily   controlled by changing the base. Changing the base from   Cs2CO3    to DBU changed the diastereomeric ratio (trans/cis)   from 3/2 to 9/1. Moreover, the treatment of the   trans   isomer with DBU showed a complete conversion to the   corresponding   cis   isomer.

      Address (URL): http://pubs.acs.org/doi/abs/10.1021/jo801818p