Synthesis and Spectral Properties of Macrocyclic Compounds Containing 1,3,4‐Thiadiazole Moeties Connected by a Carbon–Oxygen Bridge

Abstract

The syntheses of 1∶1‐macrocycles 3 (n=1), unsymmetrical macrocycle 5 (m=0, n=1), 2∶2‐macrocycle 5 (m=n=1 and 2), 3∶3 macrocycle 7, and several open‐chain ethereal compounds prepared from 2,5‐dichloro‐1,3,4‐thiadiazole 1 and various polyethylene glycols dianions are described. Structural proofs are afforded by their mass and NMR spectral features. The quaternization studies of a few macrocycles with methyl iodide at elevated temperature furnished a diketo derivative 8 through a facile Hilbert–Johnson reaction.

Keywords:

• Hilbert–Johnson reaction
• macrocyclic
• polyethylene glycol
• 1,3,4‐thiadiazole

Acknowledgment

The research was supported by the Department of Science and Technology, Government of India, and University Grant Commission, New Delhi, in the form of grants from Fund for Improvement of Science & Technology Infrastructure (FIST) and Departmental Research Support (DRS) Programmes, respectively.