Hydrogen bonding and polymorphism of amino alcohol salts with quinaldinate : structural study

Podjed, Nina (author), Modec, Barbara (author)

Three amino alcohols, 3-amino-1-propanol (abbreviated as 3a1pOH), 2-amino-1-butanol (2a1bOH), and 2-amino-2-methyl-1-propanol (2a2m1pOH), were reacted with quinoline-2-carboxylic acid, known as quinaldinic acid. This combination yielded three salts, (3a1pOHH)quin (1, 3a1pOHH$^+$ = protonated 3-amino-1-propanol, quin$^−$ = anion of quinaldinic acid), (2a1bOHH)quin (2, 2a1bOHH$^+$ = protonated 2-amino-1-butanol), and (2a2m1pOHH)quin (3, 2a2m1pOHH$^+$ = protonated 2-amino-2-methyl-1-propanol). The 2-amino-1-butanol and 2-amino-2-methyl-1-propanol systems produced two polymorphs each, labeled 2a/2b and 3a/3b, respectively. The compounds were characterized by X-ray structure analysis on single-crystal. The crystal structures of all consisted of protonated amino alcohols with NH$_3$$^+$ moiety and quinaldinate anions with carboxylate moiety. The used amino alcohols contained one OH and one NH$_2$ functional group, both prone to participate in hydrogen bonding. Therefore, similar connectivity patterns were expected. This proved to be true to some extent as all structures contained the NH$_3$$^+$···$^−$OOC heterosynthon. Nevertheless, different hydrogen bonding and π···π stacking interactions were observed, leading to distinct connectivity motifs. The largest difference in hydrogen bonding occurred between polymorphs 3a and 3b, as they had only one heterosynton in common.

• Language: English
• Keywords: hydrogen bond, synthon, crystal structure, polymorphism, amino alcohols, quinaldinic acid
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: 12 str.
• Numbering: Vol. 27, iss. 3, art. 996
• PID: 20.500.12556/RUL-137360
• UDC: 544.142.4
• ISSN on article: 1420-3049
• DOI: 10.3390/molecules27030996
• COBISS.SI-ID: 96752899
• Publication date in RUL: 14.06.2022

Record is a part of a journal

• Title: Molecules
• Shortened title: Molecules
• Publisher: MDPI
• ISSN: 1420-3049
• COBISS.SI-ID: 18462981

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.02.2022

Secondary language

• Language: Slovenian
• Keywords: vodikova vez, sinton, kristalna struktura, polimorfizem, amino alkoholi, kinaldinska kislina

Projects

• Funder: ARRS - Slovenian Research Agency
• Funding programme: Young researchers

• Funder: ARRS - Slovenian Research Agency
• Project number: P1-0134
• Name: Kemija za trajnostni razvoj