Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles

Pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazole were synthesised in good to high yields from the condensation reaction of 1,3-dialdehydes with 3-aminoindazoles. The structural features of the compounds were determined by NMR (1H, 13C and 19F), FT-IR and HR-MS. The spectroscopic assignme...

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Main Authors: Ramle, Abdul Qaiyum, Tan, Sang Loon*, Tiekink, Edward R. T. *
Format: Article
Language:English
Published: MDPI 2022
Subjects:
Online Access:http://eprints.sunway.edu.my/2114/
http://eprints.sunway.edu.my/2114/1/crystals%202022%2012%201283.pdf
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author Ramle, Abdul Qaiyum
Tan, Sang Loon*
Tiekink, Edward R. T. *
author_facet Ramle, Abdul Qaiyum
Tan, Sang Loon*
Tiekink, Edward R. T. *
author_sort Ramle, Abdul Qaiyum
building SU Institutional Repository
collection Online Access
description Pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazole were synthesised in good to high yields from the condensation reaction of 1,3-dialdehydes with 3-aminoindazoles. The structural features of the compounds were determined by NMR (1H, 13C and 19F), FT-IR and HR-MS. The spectroscopic assignments were confirmed by X-ray crystallography for two derivatives, i.e., 9-Bromo-3-(pyridin-4-yl)pyrimido[1,2-b]indazole (1b) and 10-Methoxy-3-(pyridin-4-yl)pyrimido[1,2-b]indazole (1c), which further provides support for significant delocalisation of π-electron density over the entire fused ring system. The molecular packing was assessed by conventional methods together with Hirshfeld surface analyses. In 1b, the molecular packing features pyrimidyl-N–H···N(pyrimidyl), π(pyrazolyl)···π(pyrimidyl) and Br···N interactions within a two-dimensional array. In 1c, pyrimidyl-C–H···N(pyrazolyl) and pyridyl-C–H···O(methoxy) interactions feature within a three-dimensional architecture.
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spelling sunway-21142022-09-11T22:43:59Z http://eprints.sunway.edu.my/2114/ Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles Ramle, Abdul Qaiyum Tan, Sang Loon* Tiekink, Edward R. T. * QD Chemistry Pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazole were synthesised in good to high yields from the condensation reaction of 1,3-dialdehydes with 3-aminoindazoles. The structural features of the compounds were determined by NMR (1H, 13C and 19F), FT-IR and HR-MS. The spectroscopic assignments were confirmed by X-ray crystallography for two derivatives, i.e., 9-Bromo-3-(pyridin-4-yl)pyrimido[1,2-b]indazole (1b) and 10-Methoxy-3-(pyridin-4-yl)pyrimido[1,2-b]indazole (1c), which further provides support for significant delocalisation of π-electron density over the entire fused ring system. The molecular packing was assessed by conventional methods together with Hirshfeld surface analyses. In 1b, the molecular packing features pyrimidyl-N–H···N(pyrimidyl), π(pyrazolyl)···π(pyrimidyl) and Br···N interactions within a two-dimensional array. In 1c, pyrimidyl-C–H···N(pyrazolyl) and pyridyl-C–H···O(methoxy) interactions feature within a three-dimensional architecture. MDPI 2022-09-09 Article PeerReviewed text en cc_by_nc_4 http://eprints.sunway.edu.my/2114/1/crystals%202022%2012%201283.pdf Ramle, Abdul Qaiyum and Tan, Sang Loon* and Tiekink, Edward R. T. * (2022) Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles. Crystals, 12 (9). ISSN 2073-4352 https://www.mdpi.com/2073-4352/12/9/1283 10.3390/cryst12091283
spellingShingle QD Chemistry
Ramle, Abdul Qaiyum
Tan, Sang Loon*
Tiekink, Edward R. T. *
Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles
title Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles
title_full Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles
title_fullStr Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles
title_full_unstemmed Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles
title_short Synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles
title_sort synthesis and crystallographic characterisation of pyridyl- and indoleninyl-substituted pyrimido[1,2-b]indazoles
topic QD Chemistry
url http://eprints.sunway.edu.my/2114/
http://eprints.sunway.edu.my/2114/
http://eprints.sunway.edu.my/2114/
http://eprints.sunway.edu.my/2114/1/crystals%202022%2012%201283.pdf