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Updated: Oct 1, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Synthesis and structures of three benzoannelated macrobicyclic diamides
Gary L N Smith1, Richard W Taylor2
1Department of Chemistry, San Diego Miramar College, San Diego, CA 92126, USA.
Abstract:
We report the synthesis and structures of 9,10,20,21-tetrahydro-5,14-(ethanooxyethano)dibenzo[e,q][1,4,10,13,7,16]tetraoxadiazacyclooctadecine-6,13-dione [systematic name: 8,11,21,24,29-pentaoxa-1,18-diazatetracyclo[16.8.5.02,7.012,17]hentriaconta-2,4,6,12(17),13,15-hexaene-19,26-dione C24H28N2O8, I], 6,7,9,10,12,13,20,21-octahydro-5,14-(ethanooxyethano)dibenzo[e,q][1,4,10,13,7,16]tetraoxadiazacyclooctadecine-23,27-dione (8,11,21,24,29-pentaoxa-1,18-diazatetracyclo[16.8.5.02,7.012,17]hentriaconta-2,4,6,12,14,16-hexaene-27,31-dione; C24H28N2O7, II), and 9,10,20,21-tetrahydro-5,14-(ethanooxyethanooxyethano)dibenzo[e,q][1,4,10,13,7,16]tetraoxadiazacyclooctadecine-6,13-dione [8,11,21,24,29,32-hexaoxa-1,18-diazatetracyclo[16.8.8.02,7.012,17]tetratriaconta-2,4,6,12(17),13,15-hexaene-19,26-dione; C26H32N2O7, III]. All three compounds are made up of two tertiary diamides and are composed of two 15-membered rings with N2O3 donor sets and one 18-membered ring with an N2O4 donor set (compounds I and II) or three 18-membered rings with N2O4 donor sets (compound III). The solid-state structures of compounds I and II show little effects from the movement of the amide groups. However, compound III has a larger cavity and a different orientation of donor atoms in comparison to compounds I and II.
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