000119657 001__ 119657
000119657 005__ 20230519145523.0
000119657 0247_ $$2doi$$a10.1021/acs.joc.1c01458
000119657 0248_ $$2sideral$$a126397
000119657 037__ $$aART-2021-126397
000119657 041__ $$aeng
000119657 100__ $$aSierra, S
000119657 245__ $$aReactivity of (Z)-4-Aryliden-5(4H)-thiazolones: [2+2]-Photocycloaddition, Ring-Opening Reactions, and Influence of the Lewis Acid BF3
000119657 260__ $$c2021
000119657 5060_ $$aAccess copy available to the general public$$fUnrestricted
000119657 5203_ $$aThe irradiation of (Z)-2-phenyl-4-aryliden-5(4H)thiazolones 2 with blue light (465 nm) in CH2Cl2 solution promotes [2 + 2]-photocycloaddition of the exocyclic C=C bonds and the formation of the dispirocyclobutanes 3. This reaction takes place with high stereoselectivity, given that the epsilon-isomer (1, 3 head-to-tail syn coupling) is formed in more than 90% yield in most of the cases. However, irradiation of 5(4H)-thiazolones 2 with blue light (456 nm) in dry MeOH in the presence of BF3 center dot OEt2 leads to the monospirocyclobutanes 4 with full stereoselectivity, also affording the epsilon-isomer. A ring-opening reaction of only one of the thiazolone rings appears to have taken place in 4 upon methanolysis, leading to the corresponding ester and thioamide groups. The treatment of free 4-aryliden-5(4H)-thiazolones 2 with a base in alcohol (NaOR/ROH) also produces a ring-opening reaction of the heterocycle by methanolysis, although, under these reaction conditions, further intramolecular S-attack at the exocyclic C(H)=C bond and cyclization is observed, forming the dihydrothiazoles 5 or 6 as mixtures of cis (RS/SR)- and trans (RR/SS)-isomers with high diastereomeric excess. trans-(RR/SS)-Dihydrothiazoles 6 can be isolated as pure diastereoisomers by column chromatography. Surprisingly, dihydrothiazoles 5 can also be obtained by the treatment of 4-aryliden-5(4H)-thiazolones 2 with BF3 center dot OEt2 in methanol in the absence of a base.
000119657 536__ $$9info:eu-repo/grantAgreement/ES/DGA/E07-20R$$9info:eu-repo/grantAgreement/ES/AEI/PID2019-104379RB-C21$$9info:eu-repo/grantAgreement/ES/AEI/PID2019-106394GB-I00$$9info:eu-repo/grantAgreement/ES/DGA/E19-20R
000119657 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000119657 590__ $$a4.198$$b2021
000119657 591__ $$aCHEMISTRY, ORGANIC$$b12 / 57 = 0.211$$c2021$$dQ1$$eT1
000119657 592__ $$a0.983$$b2021
000119657 593__ $$aOrganic Chemistry$$c2021$$dQ1
000119657 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000119657 700__ $$aDalmau, D$$uUniversidad de Zaragoza
000119657 700__ $$aHiguera, S
000119657 700__ $$aCortes, D
000119657 700__ $$0(orcid)0000-0001-9522-5840$$aCrespo, O$$uUniversidad de Zaragoza
000119657 700__ $$aJimenez, AI
000119657 700__ $$aPop, A
000119657 700__ $$aSilvestru, C
000119657 700__ $$0(orcid)0000-0001-9779-5820$$aUrriolabeitia, EP
000119657 7102_ $$12010$$2760$$aUniversidad de Zaragoza$$bDpto. Química Inorgánica$$cÁrea Química Inorgánica
000119657 773__ $$g86, 17 (2021), 12119-12140$$pJ. org. chem.$$tJournal of Organic Chemistry$$x0022-3263
000119657 8564_ $$s3762052$$uhttps://zaguan.unizar.es/record/119657/files/texto_completo.pdf$$yVersión publicada
000119657 8564_ $$s2833472$$uhttps://zaguan.unizar.es/record/119657/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000119657 909CO $$ooai:zaguan.unizar.es:119657$$particulos$$pdriver
000119657 951__ $$a2023-05-18-15:24:19
000119657 980__ $$aARTICLE