{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:44:56Z","timestamp":1760060696298,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2025,9,12]],"date-time":"2025-09-12T00:00:00Z","timestamp":1757635200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>This study focuses on the synthesis, properties, and comparative analysis of new flame-retardant compounds: coumarins and isophosphinolines. These compounds feature a diarylphosphine oxide (DAPO) substituent at the \u03b2-position relative to both the carbonyl and the phosphoryl groups. Various derivatives with halogens, phosphorus, and\/or aromatics substituents were synthetized and their thermal stability and flammability were evaluated at the microscale by thermogravimetric analysis (TGA) and pyrolysis\u2013combustion flow calorimetry (PCFC) in order to identify the most promising molecules for use as flame-retardant (FR) additives or comonomers. FTIR-coupled PCFC analysis was also carried out to study the combustion profiles of the molecules. Beyond the confirmation of some expected trends, such as the char promotion of phosphorus and flame inhibition of halogens, the study revealed some unexpected findings that warrant further investigation. These include the prominent role of the chlorine substitution position on the aromatic ring, as well as significant differences in FR performance between diastereoisomers.<\/jats:p>","DOI":"10.3390\/molecules30183717","type":"journal-article","created":{"date-parts":[[2025,9,15]],"date-time":"2025-09-15T10:51:33Z","timestamp":1757933493000},"page":"3717","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Synthesis and Comparison of the Flame-Retardant Properties of Phosphorylated-Coumarins and Phosphorylated-Isophosphinolines"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-6958-8842","authenticated-orcid":false,"given":"Issaka","family":"Ibrahim Abdou Rachid","sequence":"first","affiliation":[{"name":"ICGM, Univ Montpellier, ENSCM, CNRS, 34090 Montpellier, France"},{"name":"University Abdou Moumouni of Niamey, Niamey 10896, Niger"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1685-584X","authenticated-orcid":false,"given":"Karen-Pacelye","family":"Mengue Me Ndong","sequence":"additional","affiliation":[{"name":"ICGM, Univ Montpellier, ENSCM, CNRS, 34090 Montpellier, France"},{"name":"Universit\u00e9 des Sciences et Techniques de Masuku, Franceville 942, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdoul Razak","family":"Halidou Dougourikoye","sequence":"additional","affiliation":[{"name":"University Abdou Moumouni of Niamey, Niamey 10896, Niger"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mina","family":"Hariri","sequence":"additional","affiliation":[{"name":"ICGM, Univ Montpellier, ENSCM, CNRS, 34090 Montpellier, France"},{"name":"Department of Chemistry, K. N. Toosi University of Technology, Tehran 19991-43344, Iran"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4099-2919","authenticated-orcid":false,"given":"Gabin","family":"Mwande-Maguene","sequence":"additional","affiliation":[{"name":"Universit\u00e9 des Sciences et Techniques de Masuku, Franceville 942, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacques","family":"Lebibi","sequence":"additional","affiliation":[{"name":"Universit\u00e9 des Sciences et Techniques de Masuku, Franceville 942, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fatemeh","family":"Darvish","sequence":"additional","affiliation":[{"name":"Department of Chemistry, K. N. Toosi University of Technology, Tehran 19991-43344, Iran"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ilagouma Amadou","family":"Tidjani","sequence":"additional","affiliation":[{"name":"University Abdou Moumouni of Niamey, Niamey 10896, Niger"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Virieux","sequence":"additional","affiliation":[{"name":"ICGM, Univ Montpellier, ENSCM, CNRS, 34090 Montpellier, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3688-2047","authenticated-orcid":false,"given":"Jean-Luc","family":"Pirat","sequence":"additional","affiliation":[{"name":"ICGM, Univ Montpellier, ENSCM, CNRS, 34090 Montpellier, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tahar","family":"Ayad","sequence":"additional","affiliation":[{"name":"ICGM, Univ Montpellier, ENSCM, CNRS, 34090 Montpellier, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Loic","family":"Dumazert","sequence":"additional","affiliation":[{"name":"Polymers Composites and Hybrids (PCH), IMT Mines Ales, 30319 Ales, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4567-1831","authenticated-orcid":false,"given":"Arie","family":"van der Lee","sequence":"additional","affiliation":[{"name":"IEM, University Montpellier, ENSCM, CNRS, 34095 Montpellier, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4403-4547","authenticated-orcid":false,"given":"Claire","family":"Negrell","sequence":"additional","affiliation":[{"name":"ICGM, Univ Montpellier, ENSCM, CNRS, 34090 Montpellier, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6487-7299","authenticated-orcid":false,"given":"Rodolphe","family":"Sonnier","sequence":"additional","affiliation":[{"name":"Polymers Composites and Hybrids (PCH), IMT Mines Ales, 30319 Ales, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2608","DOI":"10.1016\/j.polymer.2009.03.047","article-title":"A molecular basis for polymer flammability","volume":"50","author":"Lyon","year":"2009","journal-title":"Polymer"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"548","DOI":"10.1002\/app.11466","article-title":"Molar Group Contributions to Polymer Flammability","volume":"87","author":"Walters","year":"2003","journal-title":"J. Appl. Polym. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1016\/j.polymer.2016.01.046","article-title":"Predicting the flammability of polymers from their chemical structure: An improved model based on group contributions","volume":"86","author":"Sonnier","year":"2016","journal-title":"Polymer"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2182","DOI":"10.1016\/j.combustflame.2013.04.009","article-title":"Study of the combustion efficiency of polymers using a pyrolysis\u2013combustion flow calorimeter","volume":"160","author":"Sonnier","year":"2013","journal-title":"Combust. Flame"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1501","DOI":"10.1002\/pen.20871","article-title":"Screening Flame Retardants for Plastics Using Microscale Combustion Calorimetry","volume":"47","author":"Lyon","year":"2007","journal-title":"Polym. Eng. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1016\/j.polymdegradstab.2009.11.047","article-title":"Investigation of the flammability of different textile fabrics using micro-scale combustion calorimetry","volume":"95","author":"Yang","year":"2010","journal-title":"Polym. Degrad. Stab."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Annunziata, F., Pinna, C., Dallavalle, S., Tamborini, L., and Pinto, A. (2020). An Overview of Coumarin as a Versatile and Readily Accessible Scaffold with Broad-Ranging Biological Activities. Int. J. Mol. Sci., 21.","DOI":"10.3390\/ijms21134618"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Wu, Y., Xu, J., Liu, Y., Zeng, Y., and Wu, G. (2020). A Review on anti-tumor mechanisms of coumarins. Front. Oncol., 10.","DOI":"10.3389\/fonc.2020.592853"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"8178","DOI":"10.1016\/j.tet.2015.08.026","article-title":"Silver-catalyzed direct Csp2-H radical phosphorylation of coumarins with H-phosphites","volume":"71","author":"Yuan","year":"2015","journal-title":"Tetrahedron"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"597","DOI":"10.1016\/S0223-5234(03)00086-2","article-title":"Cytotoxic effects alkylating properties and molecular modelling of coumarin derivatives and their phosphonic analogues","volume":"38","author":"Budzisz","year":"2003","journal-title":"Eur. J. Med. Chem."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1713","DOI":"10.1002\/jhet.5570220648","article-title":"An efficient synthesis of diethyl coumarin-3-phosphonates","volume":"22","author":"Singh","year":"1985","journal-title":"J. Heterocycl. Chem."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2274","DOI":"10.1016\/j.tetlet.2010.02.108","article-title":"A simple and effective synthesis of activated vinylphosphonates from 3-methoxy-2-diethoxyphosphorylacrylate","volume":"51","author":"Janecki","year":"2010","journal-title":"Tetrahedron Lett."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"6266","DOI":"10.1021\/ol4031167","article-title":"Regioselective Palladium-Catalyzed Phosphonation of Coumarins with Dialkyl H Phosphonates via C-H Functionalization","volume":"15","author":"Mi","year":"2013","journal-title":"Org. Lett."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2773","DOI":"10.1002\/adsc.201700293","article-title":"Metal-Free Visible-Light-Promoted Synthesis of 3-Phosphorylated Coumarins via radical C-P\/C-C Bond Formation","volume":"359","author":"Liu","year":"2017","journal-title":"Adv. Synth. Catal."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1394","DOI":"10.1021\/acs.orglett.7b00299","article-title":"Direct Phosphonation of Quinolinones and Coumarins Driven by the Photochemical Activity of Substrates and Products","volume":"19","author":"Kim","year":"2017","journal-title":"Org. Lett."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1378","DOI":"10.1021\/jo202183u","article-title":"Phospha-Michael Additions to Activated Internal Alkenes: Steric and Electronic Effects","volume":"77","author":"Lenker","year":"2012","journal-title":"J. Org. Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5411","DOI":"10.1002\/adsc.202001054","article-title":"Catalyst- and Additive-Free Decarboxylative C-4 Phosphorylation of Coumarin-3-Carboxylic Acids at Ambient Conditions","volume":"362","author":"Brahmachari","year":"2020","journal-title":"Adv. Synth. Catal."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1016\/j.polymer.2017.09.012","article-title":"Prediction of thermosets flammability using a model based on group contributions","volume":"127","author":"Sonnier","year":"2017","journal-title":"Polymer"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Mengue Me Ndong, K.P., Hariri, M., Mwande-Maguene, G., Lebibi, J., Darvish, F., Safi, C., Abdelli, K., Da\u00efch, A., Negrell, C., and Sonnier, R. (2024). Palladium-Catalyzed C-H functionalization and flame-retardant properties of isophosphinolines. Molecules, 29.","DOI":"10.3390\/molecules29215104"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Roncucci, D., Aug\u00e9, M.-O., Dul, S., Chen, J., Gooneie, A., Rentsch, D., Lehner, S., Jovic, M., Rippl, A., and Ayala, V. (2024). Coumarin-DPPO a new bio-based phosphorus additive for poly(lactic acid): Processing and flame retardant application. Polym. Degrad. Stab., 223.","DOI":"10.1016\/j.polymdegradstab.2024.110737"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"5817","DOI":"10.1016\/S0040-4039(02)01177-2","article-title":"t-BuOK-catalyzed addition of phosphines to functionalized alkenes: A convenient synthesis of polyfunctional phosphine derivatives","volume":"43","author":"Bunlaksananusorn","year":"2002","journal-title":"Tetrahedron Lett."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"5462","DOI":"10.1039\/C7OB01104K","article-title":"t-BuOK-mediated reductive addition of P(O)\u2013H compounds to terminal alkynes forming \u03b2-arylphosphine oxides","volume":"15","author":"Zhang","year":"2017","journal-title":"Org. Biomol. Chem."},{"key":"ref_23","unstructured":"Bruker (2012). APEX3, XPREP and SAINT, Bruker AXS Inc."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1306","DOI":"10.1107\/S0021889813020049","article-title":"Charge flipping for routine structure solution","volume":"46","year":"2013","journal-title":"J. Appl. Crystallogr."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1107\/S0021889807029238","article-title":"SUPERFLIP\u2014A Computer Program for the Solution of Crystal Structures by Charge Flipping in Arbitrary Dimensions","volume":"40","author":"Palatinus","year":"2007","journal-title":"J. Appl. Crystallogr."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Betteridge, P.W., Carruthers, J.R., Cooper, R.I., Prout, K., and Watkin, D.J. (2003). CRYSTALS version 12: Software for guided crystal structure analysis. J. Appl. Crystallogr., 36.","DOI":"10.1107\/S0021889803021800"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"387","DOI":"10.2174\/1570178615666171227144555","article-title":"Synthesis of secondary phosphine oxides by substitution at phosphorus by grignard reagents","volume":"15","author":"Tripolszky","year":"2018","journal-title":"Lett. Org. Chem."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"8495","DOI":"10.1021\/acsomega.1c00160","article-title":"Direct 1,1-bisphosphonation of isocyanides: Atom- and step-economical access to bisphosphinoylaminomethanes","volume":"6","author":"Yuan","year":"2021","journal-title":"ACS Omega"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"7433","DOI":"10.1002\/chem.201701414","article-title":"Outer-sphere reactivity shift of secondary phosphine oxide-based nickel complexes: From ethylene hydrophosphinylation to oligomerization","volume":"23","author":"Lhermet","year":"2017","journal-title":"Chem. Eur. J."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"10887","DOI":"10.1021\/acscatal.3c02870","article-title":"Nickel-Catalyzed Enantioselective Hydrophosphinylation of 2-Azadienes to Access Enantioenriched \u03b1-Aminophosphine Oxides","volume":"13","author":"Duan","year":"2023","journal-title":"ACS Catal."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2597","DOI":"10.1021\/acs.orglett.9b00569","article-title":"Preparation of O-Protected Cyanohydrins by Aerobic Oxidation of \u03b1-Substituted Malononitriles in the Presence of Diarylphosphine","volume":"21","author":"Zhang","year":"2019","journal-title":"Oxides. Org. Lett."},{"key":"ref_32","unstructured":"He, Z.K., and Tang, C.L. (2024). D-A Type Triarylphosphine Compound and Synthetic Method and Application Thereof. (1149207774 A), C.N. Patent."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1002\/fam.810040202","article-title":"Estimation of rate of heat release by means of oxygen consumption measurements","volume":"4","author":"Huggett","year":"1980","journal-title":"Fire Mater."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Sonnier, R. (2022). Microscale forced combustion: Pyrolysis-combustion flow calorimetry (PCFC). Analysis of Flame Retardancy in Polymer Science, Elsevier. Chapter 3.","DOI":"10.1016\/B978-0-12-824045-8.00003-4"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1398","DOI":"10.1016\/j.combustflame.2013.11.011","article-title":"FTIR\u2013PCFC coupling: A new method for studying the combustion of polymers","volume":"161","author":"Sonnier","year":"2014","journal-title":"Combust. Flame"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"855","DOI":"10.1016\/j.combustflame.2014.08.008","article-title":"A microscale combustion calorimeter study of gas phase combustion of polymers","volume":"162","author":"Walters","year":"2015","journal-title":"Combust. Flame"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"8495","DOI":"10.1016\/j.polymer.2006.10.022","article-title":"Influence of the oxidation state of phosphorus on the decomposition and fire behaviour of flame-retarded epoxy resin composites","volume":"47","author":"Braun","year":"2006","journal-title":"Polymer"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"5012","DOI":"10.1016\/j.polymer.2005.04.025","article-title":"Flame retardant aircraft epoxy resins containing phosphorus","volume":"46","author":"Hergenrother","year":"2005","journal-title":"Polymer"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1663","DOI":"10.1016\/0584-8539(72)80138-7","article-title":"Infrared spectra of aromatic acid halides","volume":"28","author":"Jalhoom","year":"1972","journal-title":"Spectrochim. Acta Part A Mol. Spectrosc."}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/30\/18\/3717\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:44:49Z","timestamp":1760035489000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/30\/18\/3717"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,12]]},"references-count":39,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["molecules30183717"],"URL":"https:\/\/doi.org\/10.3390\/molecules30183717","relation":{},"ISSN":["1420-3049"],"issn-type":[{"type":"electronic","value":"1420-3049"}],"subject":[],"published":{"date-parts":[[2025,9,12]]}}}