0000000001312671
AUTHOR
João R. Vale
showing 7 related works from this author
Lewis Base Catalyzed Intramolecular Reduction of Salicylaldehydes by Pinacol-Derived Chlorohydrosilane
2018
Synthesis of silacyclopent-2-en-4-ols via intramolecular [2 + 2] photocycloaddition of benzoyl(allyl)silanes
2019
Organosilicon compounds are versatile units with a wide range of uses from medicinal chemistry to the field of organic electronics. An unprecedented method for the synthesis of novel diaryl-substituted silacyclopentenols via blue-light promoted intramolecular [2 + 2] photocycloaddition of acyl silanes is herein disclosed. Additionally, the present findings demonstrate the influence of the olefin substituents in controlling the regioselectivity of the intramolecular Paterno–Buchi reaction, providing silacycles different from previously reported ones. The high degree of functionalization of these compounds makes them attractive precursors to other synthetically challenging silacyclopentanes.
Synthesis of 6,12-Disubstituted Methanodibenzo[b,f][1,5]dioxocins : Pyrrolidine Catalyzed Self-Condensation of 2′-Hydroxyacetophenones
2019
The preparation of unprecedented 6,12-disubstituted methanodibenzo[b,f][1,5]dioxocins from pyrrolidine catalyzed self-condensation of 2′-hydroxyacetophenones is herein described. This method provides easy access to this highly bridged complex core, resulting in construction of two C–O and two C–C bonds, a methylene bridge and two quaternary centers in a single step. The intricate methanodibenzo[b,f][1,5]dioxocin compounds were obtained in up to moderate yields after optimization of the reaction conditions concerning solvent, reaction times and the use of additives. Several halide substituted methanodibenzo[b,f][1,5]dioxocins could be prepared from correspondent 2′-hydroxyacetophenones.
Pot-Economy Autooxidative Condensation of 2-Aryl-2-lithio-1,3-dithianes
2018
The autoxidative condensation of 2-aryl-2-lithio-1,3-dithianes is here reported. Treatment of 2-aryl-1,3-dithianes with n-BuLi in the absence of any electrophile leads to condensation of three molecules of 1,3-dithianes and formation of highly functionalized α-thioether ketones orthothioesters in 51-89% yields upon air exposure. The method was further expanded to benzaldehyde dithioacetals, affording corresponding orthothioesters and α-thioether ketones in 48-97% yields. The experimental results combined with density functional theory studies support a mechanism triggered by the autoxidation of 2-aryl-2-lithio-1,3-dithianes to yield a highly reactive thioester that undergoes condensation wi…
CCDC 1935511: Experimental Crystal Structure Determination
2019
Related Article: João R. Vale, Arto Valkonen, Carlos A. M. Afonso, Nuno R. Candeias|2019|Org.Chem.Front.|6|3793|doi:10.1039/C9QO01028A
CCDC 1922829: Experimental Crystal Structure Determination
2019
Related Article: Benedicta Assoah, Vesa Riihonen, João R. Vale, Arto Valkonen, Nuno R. Candeias|2019|Molecules|24|2405|doi:10.3390/molecules24132405
CCDC 1935510: Experimental Crystal Structure Determination
2019
Related Article: João R. Vale, Arto Valkonen, Carlos A. M. Afonso, Nuno R. Candeias|2019|Org.Chem.Front.|6|3793|doi:10.1039/C9QO01028A