abstract
The reaction of dithiooxamide with aromatic aldehydes is a well-known method for the preparation of thiazolo[5,4-d]thiazoles (TzTz). However, we report here that, using adequately substituted 2-halobenzaldehydes, this reaction may afford selectively thiazolo[5,4-c]isoquinolines (TzIQ) or mixtures of TzTz and TzIQ. The use of lanthanum(iii) triflate as the catalyst favors the formation of TzIQ. The results obtained using a large number of substituted benzaldehydes showed that the nature, number and position of halogen atoms and other substituents on the aldehyde have a great impact on the reaction outcome. The structures of six TzTz and six TzIQ were unveiled by single-crystal X-ray diffraction.
keywords
SULFUR EXTRUSION; DERIVATIVES; THIAZOLOISOQUINOLINES; INHIBITOR; FTSZ; SEMICONDUCTORS; FLUORESCENCE; CYCLIZATION; QUINOLINES; PC190723
subject category
Chemistry
authors
Costa, LD; Guieu, S; Faustino, MDF; Tome, AC
our authors
Samuel Jacques André Guieu
Junior Researcheracknowledgements
Thanks are due to FundacAo para a Ciencia e a Tecnologia (FCT) for the financial support to project PTDC/QEQ-QOR/6160/2014, the LAQV-REQUIMTE (UIDB/50006/2020), and the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT UID/CTM/50011/2019), through national funds and when applicable co-financed by the FEDER, within the PT2020 Partnership Agreement. L. D. Costa thanks FCT for her doctoral grant (SFRH/PD/BD/114578/2016). S. Guieu also thanks the funding from national funds (OE), through FCT, in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19.