Use of 1,3-dipolar reactions for the preparation of SF5-substituted five-membered ring heterocycles. Pyrroles and thiophenes

Dolbier, William R.; Zheng, Zhaoyun

doi:10.1016/j.jfluchem.2011.03.017

Cited by 32 publications

(22 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[9] However,t he preparation of SF 5 -substituted pyridines remains ac hallenge. [13] In 2015, Kanishchev and Dolbier reported the first general method for the synthesis of ortho-SF 5 -substituted pyridines on the basis of the method described by Umemoto et al,[10b] in which 2,2'dipyridyl disulfides interacted with the KF/Cl 2 /MeCN system to afford SF 4 Cl-pyridines.F or the further transformation of these sulfur chlorotetrafluorides into SF 5 -pyridines,s ilver fluoride (AgF) was found to be the most suitable reagent (Scheme 1). [13] In 2015, Kanishchev and Dolbier reported the first general method for the synthesis of ortho-SF 5 -substituted pyridines on the basis of the method described by Umemoto et al,[10b] in which 2,2'dipyridyl disulfides interacted with the KF/Cl 2 /MeCN system to afford SF 4 Cl-pyridines.F or the further transformation of these sulfur chlorotetrafluorides into SF 5 -pyridines,s ilver fluoride (AgF) was found to be the most suitable reagent (Scheme 1).…”

mentioning

confidence: 99%

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ⁶‐sulfanyl‐Substituted Pyridines

et al. 2016

View full text Add to dashboard Cite

Although there are ways to synthesize ortho-pentafluoro-λ(6) -sulfanyl (SF5 ) pyridines, meta- and para-SF5 -substituted pyridines are rare. We disclose herein a general route for their synthesis. The fundamental synthetic approach is the same as reported methods for ortho-SF5 -substituted pyridines and SF5 -substituted arenes, that is, oxidative chlorotetrafluorination of the corresponding disulfides to give pyridylsulfur chlorotetrafluorides (SF4 Cl-pyridines), followed by chloride/fluoride exchange with fluorides. However, the trick in this case is the presence on the pyridine ring of at least one fluorine atom, which is essential for the successful transformation of the disulfides into m-and p-SF5 -pyridines. After enabling the synthesis of an SF5 -substituted pyridine, ortho-F groups can be efficiently substituted by C, N, S, and O nucleophiles through an SN Ar pathway. This methodology provides access to a variety of previously unavailable SF5 -substituted pyridine building blocks.

show abstract

mentioning

confidence: 99%

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ⁶‐sulfanyl‐Substituted Pyridines

et al. 2016

View full text Add to dashboard Cite

show abstract

“…These compounds have always been prepared from a SF 5 ‐substituted aryl precursor, exploiting well‐known cyclization techniques to build heterocyclic systems of indole,5a,b indazole,5c benzimidazole,5d–f benzoxazole,5g benzisoxazole,5h benzothiophene,5a benzothiazole,5i benzotriazole,5d quinoline,3d,e,h, 5h quinoxaline,5d and quinazoline 5h. The second smaller group comprises monocyclic aromatic SF 5 ‐substituted heterocycles: pyrroles,5j,k furans,5l,m thiophenes,5j,k pyrazoles,5n,o isoxazoles,5m and triazoles 5o–q. Routes to those heterocycles utilized either 1,3‐dipolar cycloaddition reactions with SF 5 ‐substituted alkynes or retro‐Diels–Alder reactions of bridged SF 5 ‐containing precursors.…”

Section: Methodsmentioning

confidence: 99%

Synthesis and Characterization of 2‐Pyridylsulfur Pentafluorides

Kanishchev

2014

Angewandte Chemie

Self Cite

View full text Add to dashboard Cite

Current approaches to prepare SF5‐substituted heterocycles during the synthesis of targeted heterocyclic compounds require the use of SF5‐functionalized aryl or alkyne reagents or SF5Cl as a source of the SF5 functional group. Herein we report that excess oxidative fluorination of 2,2′‐dipyridyl disulfide with a KF/Cl2/MeCN system leads to the formation of thirteen new 2‐pyridylsulfur chlorotetrafluorides (2‐SF4Cl‐pyridines). These molecules are found to undergo further chlorine–fluorine exchange reactions by treatment with silver(I) fluoride enabling ready access to a series of ten new substituted 2‐pyridylsulfur pentafluorides (2‐SF5‐pyridines). This is the first preparatively simple and readily scalable example of the transformation of an existing heterocyclic sulfur functionality to prepare SF5‐substituted heterocycles.

show abstract

“…Compounds (4), (5), (11), (12) and (13) are energetic compounds containing one furazan ring. The HOF of compound (4) is −1164.3 kJ/mol.…”

Section: Heats Of Formationmentioning

confidence: 99%

Theoretical studies on energetic materials bearing pentaflurosulphyl (SF 5 ) groups

Cui

et al. 2014

J Chem Sci

View full text Add to dashboard Cite

Heats of formation (HOF) for a series of energetic materials containing SF 5 group were studied by density functional theory. Results show that HOFs increase with the augmention of field effects of substituted groups. Addition of furazan or furoxan ring increases HOF of the energetic materials. All the SF 5-containing compounds have densities which are ∼0.19 g/cm 3 higher than those containing-NH 2 group. S-F bond is the trigger bond for the thermolysis process in the title compounds and bond dissociation energies of the weakest bonds range from 351.1 to 388.3 kJ/mol. Detonation velocities (D) and pressures (P) are evaluated by Kamlet-Jacobs equations with the calculated densities and HOFs. Results show that increasing the amount of furazan rings results in a larger D and P. Considering the detonation performance and thermal stability, eight compounds may be considered as potential candidates for high-energy density materials.

show abstract

Use of 1,3-dipolar reactions for the preparation of SF5-substituted five-membered ring heterocycles. Pyrroles and thiophenes

Cited by 32 publications

References 26 publications

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ⁶‐sulfanyl‐Substituted Pyridines

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ⁶‐sulfanyl‐Substituted Pyridines

Synthesis and Characterization of 2‐Pyridylsulfur Pentafluorides

Theoretical studies on energetic materials bearing pentaflurosulphyl (SF 5 ) groups

Contact Info

Product

Resources

About

Use of 1,3-dipolar reactions for the preparation of SF5-substituted five-membered ring heterocycles. Pyrroles and thiophenes

Cited by 32 publications

References 26 publications

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ6‐sulfanyl‐Substituted Pyridines

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ6‐sulfanyl‐Substituted Pyridines

Synthesis and Characterization of 2‐Pyridylsulfur Pentafluorides

Theoretical studies on energetic materials bearing pentaflurosulphyl (SF 5 ) groups

Contact Info

Product

Resources

About

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ⁶‐sulfanyl‐Substituted Pyridines

Importance of a Fluorine Substituent for the Preparation of meta‐ and para‐Pentafluoro‐λ⁶‐sulfanyl‐Substituted Pyridines