Silyl Esters as Reactive Intermediates in Organic Synthesis DOI
Marc J. Adler, Melissa C. D’Amaral, Keith G. Andrews

et al.

Synthesis, Journal Year: 2023, Volume and Issue: 55(20), P. 3209 - 3238

Published: April 28, 2023

Abstract Silyl esters have been exploited as metastable reaction intermediates, both purposefully and unintentionally, since at least the 1960s. Their reactivity is broadly related to substituents on silicon, in this way their properties can be readily modulated. unique profiles that used generate downstream products of a range functionalities, because many excellent methods for synthesis variety value-added chemicals developed. Furthermore, frequent use hydrosilanes terminal reductants catalytic processes, silyl ester intermediates are likely more commonly utilized by synthetic chemists than currently realized. This review comprehensively summarizes reactions known take advantage reactive discusses examples proceed an unanticipated manner through intermediates. 1 Introduction 2 Synthesis Esters 3 Making Amides from 3.1 Amidation Using Chlorosilanes 3.2 Azasilanes 3.3 Oxysilanes 3.4 Hydrosilanes 3.5 Amine Formation via Amidation/Reduction 3.6 Miscellaneous 4 Mechanistic Investigations 4.1 Mechanism 4.2 4.3 Oxy- or 5 6 Aldehydes, Alcohols, Amines, Alkanes Reduction 6.1 Aldehyde Metal-Free 6.2 Metal-Mediated 6.3 Alcohol 6.4 6.5 Alkane 7 Acid Chlorides 8 In Situ Generated Ramifications Catalysis 9 Conclusion

Language: Английский

Practical N-to-C peptide synthesis with minimal protecting groups DOI Creative Commons

Toshifumi Tatsumi,

Koki Sasamoto,

Takuya Matsumoto

et al.

Communications Chemistry, Journal Year: 2023, Volume and Issue: 6(1)

Published: Oct. 26, 2023

Accessible drug modalities have continued to increase in number recent years. Peptides play a central role as pharmaceuticals and biomaterials these new modalities. Although traditional peptide synthesis using chain-elongation from C- N-terminus is reliable, it produces large quantities of chemical waste derived protecting groups condensation reagents, which place heavy burden on the environment. Here we report an alternative N-to-C elongation strategy utilizing catalytic thioacid formation oxidative bond with main chain-unprotected amino acids under aerobic conditions. This method applicable both iterative couplings convergent fragment without requiring elaborate reagents group manipulations. A recyclable N-hydroxy pyridone additive effectively suppresses epimerization at elongating chain. We demonstrate practicality this by showcasing straightforward nonapeptide DSIP. further opens door clean atom-efficient synthesis.

Language: Английский

Citations

11

Radical C‐Glycosylation Using Photoexcitable Unprotected Glycosyl Borate DOI
Yusuke Miyamoto, Sho Murakami, Yuto Sumida

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 23, 2024

Abstract We have developed radical C‐glycosylation using photoexcitable unprotected glycosyl borate. The direct excitation of borate under visible light irradiation enabled the generation anomeric without any photoredox catalysts. in situ generated was applicable to addition such as Giese‐type and Minisci‐type reaction introduce alkyl heteroaryl groups at position. In addition, radical–radical coupling between acyl imidazolide provided C‐glycosides.

Language: Английский

Citations

4

Tantalum-Catalyzed Amidation of Amino Acid Homologues DOI
Wataru Muramatsu, Hisashi Yamamoto

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(48), P. 18926 - 18931

Published: Nov. 15, 2019

A tantalum-catalyzed solvent-free approach for the construction of amide bonds with 1-(trimethylsilyl)imidazole is developed, and mild reaction conditions are applicable to a wide variety electrophilic amino acid homologues. This delivers new class peptides in high yields without any epimerization.

Language: Английский

Citations

35

Thionyl Fluoride-Mediated One-Pot Substitutions and Reductions of Carboxylic Acids DOI
Trevor G. Bolduc, Cayo Lee,

William P. Chappell

et al.

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(11), P. 7308 - 7318

Published: May 12, 2022

Thionyl fluoride (SOF2) is an underutilized reagent that yet to be extensively studied for its synthetic applications. We previously reported it a powerful both the rapid syntheses of acyl fluorides and one-pot peptide couplings, but full scope these nucleophilic substitutions had not been explored. Herein, we report thionyl fluoride-mediated peptides amides (35 examples, 45–99% yields) were explored in our previous study. The was also expanded encompass esters (24 64–99% thioesters (11 24–96% yields). In addition, demonstrate reactions can extended beyond mild reductions carboxylic acids using NaBH4 (13 33–80%

Language: Английский

Citations

18

Silyl Esters as Reactive Intermediates in Organic Synthesis DOI
Marc J. Adler, Melissa C. D’Amaral, Keith G. Andrews

et al.

Synthesis, Journal Year: 2023, Volume and Issue: 55(20), P. 3209 - 3238

Published: April 28, 2023

Abstract Silyl esters have been exploited as metastable reaction intermediates, both purposefully and unintentionally, since at least the 1960s. Their reactivity is broadly related to substituents on silicon, in this way their properties can be readily modulated. unique profiles that used generate downstream products of a range functionalities, because many excellent methods for synthesis variety value-added chemicals developed. Furthermore, frequent use hydrosilanes terminal reductants catalytic processes, silyl ester intermediates are likely more commonly utilized by synthetic chemists than currently realized. This review comprehensively summarizes reactions known take advantage reactive discusses examples proceed an unanticipated manner through intermediates. 1 Introduction 2 Synthesis Esters 3 Making Amides from 3.1 Amidation Using Chlorosilanes 3.2 Azasilanes 3.3 Oxysilanes 3.4 Hydrosilanes 3.5 Amine Formation via Amidation/Reduction 3.6 Miscellaneous 4 Mechanistic Investigations 4.1 Mechanism 4.2 4.3 Oxy- or 5 6 Aldehydes, Alcohols, Amines, Alkanes Reduction 6.1 Aldehyde Metal-Free 6.2 Metal-Mediated 6.3 Alcohol 6.4 6.5 Alkane 7 Acid Chlorides 8 In Situ Generated Ramifications Catalysis 9 Conclusion

Language: Английский

Citations

10