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DOI: 10.1055/s-0036-1591973
Synthesis of α-Thiooximes by Addition of Thiols to N,N-Bis(oxy)-enamines: A Comparative Study of S-, N-, and O-Nucleophiles in Michael Reaction with Nitrosoalkene Species
This work was supported by the Russian Science Foundation (grant 14-50-00126).Publication History
Received: 09 February 2018
Accepted after revision: 05 March 2018
Publication Date:
11 April 2018 (online)
![](https://www.thieme-connect.de/media/synlett/201810/lookinside/thumbnails/st-2018-v0092-l_10-1055_s-0036-1591973-1.jpg)
Abstract
Nucleophilic addition of thiols to N,N-bis(oxy)enamines (nitrosoalkene acetals) produce valuable α-thiooximes in a highly efficient manner. The reaction was found to be solvent-dependent, likely because of distinct mechanisms operating in nonpolar and basic solvents (involving either Brønsted acid or Lewis base catalysis). By performing a series of competition experiments, the relative reactivity of S-, N-, and O-nucleophiles in reaction with N,N-bis(oxy)enamines was determined for the first time. Interestingly, the relative nucleophilicity was found to be highly dependent on the solvent, which allows regioselective control of these reactions by using an appropriate medium.
Supporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0036-1591973. Supporting Information contains experimental procedures, characterization data, copies of NMR and FT-IR spectra and primary data for Figure 1.
- Supporting Information
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References and Notes
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