Sulfonyl groups are widely observed in biologically relevant molecules and consequently, SO
capture is an increasingly attractive method to prepare these sulfonyl-containing compounds given the range ...of SO
-surrogates now available as alternatives to using the neat gas. This, along with the advent of photoredox catalysis, has enabled mild radical capture of SO
to emerge as an effective route to sulfonyl compounds. Here we report a photoredox-catalyzed cross-electrophile sulfonylation of aryl and alkyl bromides making use of a previously under-used amine-SO
surrogate; bis(piperidine) sulfur dioxide (PIPSO). A broad selection of alkyl and aryl bromides were photocatalytically converted to their corresponding sulfinates and then trapped with various electrophiles in a one-pot multistep procedure to prepare sulfones and sulfonamides.
Sulfonyl groups are widely observed in biologically relevant molecules and consequently, SO2 capture is an increasingly attractive method to prepare these sulfonyl‐containing compounds given the ...range of SO2‐surrogates now available as alternatives to using the neat gas. This, along with the advent of photoredox catalysis, has enabled mild radical capture of SO2 to emerge as an effective route to sulfonyl compounds. Here we report a photoredox‐catalyzed cross‐electrophile sulfonylation of aryl and alkyl bromides making use of a previously under‐used amine‐SO2 surrogate; bis(piperidine) sulfur dioxide (PIPSO). A broad selection of alkyl and aryl bromides were photocatalytically converted to their corresponding sulfinates and then trapped with various electrophiles in a one‐pot multistep procedure to prepare sulfones and sulfonamides.
A photoredox‐catalyzed one‐pot sulfone preparation is reported from alkyl bromides activated by silane‐mediated halogen atom transfer. In the process, a previously unutilized SO2 adduct bis(piperidine) sulfur dioxide – or PIPSO – was found to be the best source of SO2 for radical capture under the reaction conditions. Alkyl and aryl sulfones were prepared as well as sulfonylated APIs.
A method to assemble (hetero)aryl sulfonamides via the reductive coupling of aryl sulfinates and nitroarenes is reported. Various reducing conditions with sodium bisulfite and with or without ...tin(II) chloride in DMSO were developed using an ultrasound bath to improve reaction homogeneity and mixing. A range of (hetero)aryl sulfonamides bearing a selection of functional groups were prepared, and the mechanism of the transformation was investigated. These investigations have led us to propose the formation of nitrosoarene intermediates, which were established via an independent molecular coupling strategy.
The iron(III)‐promoted synthesis of densely‐substituted 4H‐chalcogenchromene from organochalcogen propargylamines in the presence of diaryl dichalcogenides is reported. Subsequent ...C2‐functionalization with electrophiles and potassium trifluoroborate salts via Suzuki‐Miyaura coupling reaction are also presented. A plausible mechanism based on HRMS experiments is proposed and discussed.
C‐Glycosides are valuable organic compounds in the field of medicinal chemistry due to their ubiquity inside living systems and pronounced biological activity. Herein, we describe an approach to ...alkyl‐ketones bearing glycal units via the Pd‐catalyzed carbonylative coupling of 2‐iodoglycals and alkyl and aryl halides. Examples bearing a variety of functional groups are presented as well as a mechanistic proposal for this transformation.
A versatile C(sp2)–C(sp3) carbonylative Negishi‐type reaction allowing the access to glyco‐ketones bearing alkyl and aryl groups is described in this report. The tolerance for different functional groups as well as protecting groups denote the usefulness of the methodology.
The carbonylative cross‐coupling reactions of 2‐iodoglycals with thiols and selenols in the presence of molybdenum hexacarbonyl as a solid source of carbon monoxide is described. This methodology ...permitted the synthesis of 29 C2‐glycosides bearing thioester and selenoester functionalities in moderate to excellent yields and high functional group tolerance. Moreover, this communication describes the first catalytic carbonylative coupling reaction of selenols with a carbon electrophile.
Are you in a rush? Carbonylative cross‐coupling reactions of 2‐iodoglycals with thiols (RSH) and selenols (RSeH) in the presence of molybdenum hexacarbonyl as a solid source of carbon monoxide is described. A useful methodology for the synthesis of chalcogen‐containing C2‐glycosides with high functional group tolerance.
The synthesis of amidoglucals and glucal esters in good to high yields using 2-iodo-3,4,6-tri-
O
-acetyl-
d
-glucal as a substrate, Mo(CO)
6
as a carbon monoxide source and PdCl
2
as a catalyst is ...reported. This procedure shows advantages when compared to other published methodologies, as it is carried out in one pot relying on short reaction times at mild temperatures, under ligand-free conditions and with only one equivalent of Mo(CO)
6
.
Herein we report a novel Mo-catalyzed carbonylative Sonogashira cross-coupling between 2-iodoglycals and terminal alkynes. The reaction displays major improvements compared to a related Pd-catalyzed ...procedure previously published by our group, such as utilizing unprotected sugar derivatives as starting materials and tolerance to substrates bearing chelating groups. In this work we also demonstrate the utility of the glyco-alkynone products as platform for further functionalization by synthesizing glyco-flavones
Au-catalyzed 6-
-dig cyclization.
Relative humidity is simultaneously a sensing target and a contaminant in gas and volatile organic compound (VOC) sensing systems, where strategies to control humidity interference are required. An ...unmet challenge is the creation of gas‐sensitive materials where the response to humidity is controlled by the material itself. Here, humidity effects are controlled through the design of gelatin formulations in ionic liquids without and with liquid crystals as electrical and optical sensors, respectively. In this design, the anions DCA− and Cl− of room temperature ionic liquids from the 1‐butyl‐3‐methylimidazolium family tailor the response to humidity and, subsequently, sensing of VOCs in dry and humid conditions. Due to the combined effect of the materials formulations and sensing mechanisms, changing the anion from DCA− to the much more hygroscopic Cl−, leads to stronger electrical responses and much weaker optical responses to humidity. Thus, either humidity sensors or humidity‐tolerant VOC sensors that do not require sample preconditioning or signal processing to correct humidity impact are obtained. With the wide spread of 3D‐ and 4D‐printing and intelligent devices, the monitoring and tuning of humidity in sustainable biobased materials offers excellent opportunities in e‐nose sensing arrays and wearable devices compatible with operation at room conditions.
Humidity influence in sensing of volatile organic compounds is tuned by materials design. The anions of ionic liquids tailor the gas sensing material's sensitivity to humidity, yielding either humidity‐sensitive or humidity‐tolerant odorant sensors that do not require sample preconditioning or signal processing to correct humidity impact, thereby contributing to the widespread field of artificial olfaction.
A carbonylative Sonogashira coupling approach to the synthesis of glyco-alkynones is described. Eighteen examples were obtained in moderate do nearly quantitative yields under mild conditions ...employing Mo(CO)
as a safe carbon monoxide source. Functionalization of the alkynyl moiety
cycloaddition with organic azides provided six examples of glyco-triazoles.
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