Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 27th March 2019 from 11:00 AM to 1:00 PM (GMT).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.


Issue 42, 2018
Previous Article Next Article

Umpolung cyclization reaction of N-cinnamoylthioureas in the presence of DBU

Author affiliations

Abstract

A novel regioselective cyclization reaction of N-cinnamoylthioureas leading to six- or five-membered heterocyclic compounds was developed. N-Cinnamoylthioureas in the presence of trifluoroacetic acid (TFA) underwent the well-established intramolecular cycloaddition reaction to give 2-imino-2,3,5,6-tetrahydro-4H-1,3-thiazin-4-ones in good yields. On the other hand, the reaction with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) proceeded in an unprecedented “umpolung” cyclization fashion to afford five-membered 2-imino-1,3-thiazolidin-4-ones and/or 2-thioxoimidazolidine-4-ones. The reaction was considered to occur via a cycloadduct of DBU with the cinnamoyl moiety followed by intramolecular attack of the thiourea group.

Graphical abstract: Umpolung cyclization reaction of N-cinnamoylthioureas in the presence of DBU

Back to tab navigation

Supplementary files

Publication details

The article was received on 23 Aug 2018, accepted on 03 Oct 2018 and first published on 04 Oct 2018


Article type: Paper
DOI: 10.1039/C8OB02066C
Citation: Org. Biomol. Chem., 2018,16, 7910-7919

  •   Request permissions

    Umpolung cyclization reaction of N-cinnamoylthioureas in the presence of DBU

    R. Saito, N. Uemura, H. Ishikawa, A. Magara, Y. Yoshida, T. Mino, Y. Kasashima and M. Sakamoto, Org. Biomol. Chem., 2018, 16, 7910
    DOI: 10.1039/C8OB02066C

Search articles by author

Spotlight

Advertisements