Aromatic C–H bond functionalization through organocatalyzed asymmetric intermolecular aza-Friedel–Crafts reaction: a recent update

• Anup Biswas

Beilstein J. Org. Chem. 2023, 19, 956–981, doi:10.3762/bjoc.19.72

• transition state 124, Scheme 30) [60]. In 2019, Zhou and co-workers reported an aza-Friedel–Crafts reaction between α-naphthol derivatives 17 utilizing 7-membered cyclic N-sulfonylimines 125 as electrophiles leading to the facile access of ε-sultams 126 bearing a sulfonylamine-substituted stereocenter

Development of N-F fluorinating agents and their fluorinations: Historical perspective

• Teruo Umemoto,
• Yuhao Yang and
• Gerald B. Hammond

Beilstein J. Org. Chem. 2021, 17, 1752–1813, doi:10.3762/bjoc.17.123

• -alkylarenesulfonamides, N-fluoropyridinium salts and derivatives, N-fluoroquinuclidium salts, N-fluoro-trifluoromethanesulfonimide, N-fluoro-sultams, N-fluoro-benzothiazole dioxides, N-fluoro-lactams, N-fluoro-o-benzenedisulfonimide, N-fluoro-benzenesulfonimide, 1-alkyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane salts, N

• treated with (−)-menthoxyacetyl chloride, followed by separation of the diastereomers. The chiral auxiliary was then removed with LiOH and the resulting sultams 27-5 as single enantiomers were fluorinated with 15% F2/He in the presence of KF to produce optically pure N-fluorosultam reagents (R)- and (S

• can be seen in Scheme 66, 28-4 was treated with BuLi followed by reaction with optically active menthone to give 28-5, which was converted to enantiomers of spiro sultams 28-6a and 28-6b in high yield. The spiro sultams 28-6a and -6b were separated and each was fluorinated with FClO3 to give (2'S,3R,5

A recent overview on the synthesis of 1,4,5-trisubstituted 1,2,3-triazoles

• Pezhman Shiri,
• Ali Mohammad Amani and
• Thomas Mayer-Gall

Beilstein J. Org. Chem. 2021, 17, 1600–1628, doi:10.3762/bjoc.17.114

• produce the corresponding triazole disulfide 98 [55]. A convenient route to triazole-fused sultams 104 was reported by Latyshev et al. It comprises a modified CuIAAC cycloaddition to produce intermediate sulfonamide-tethered 5-iodo-1,2,3-triazoles 103, followed by a base-mediated cyclization under

• )amine (TTTA) as ligand, and THF as solvent at 50 °C. The obtained sulfonamide-tethered 5-iodo-1,2,3-triazoles 103 were then cyclized upon heating in the presence of Cs2CO3 to give triazole-fused sultams 104. A good to excellent yield of sultam derivatives 104 containing aryl and alkyl substituents on

• converted to fused sultams (Scheme 30) [56]. Anand et al. reported a Cu-catalyzed one-pot method for the preparation of 1,2,3-triazole-fused tricyclic heterocycles 106 via an intramolecular [3 + 2]-annulation. This strategy includes the 1,6-conjugate addition of Me3SiN3 to o-alkynylated p-quinone methides

Synthesis of benzannelated sultams by intramolecular Pd-catalyzed arylation of tertiary sulfonamides

• Valentin A. Rassadin,
• Mirko Scholz,
• Anastasiia A. Klochkova,
• Armin de Meijere and
• Victor V. Sokolov

Beilstein J. Org. Chem. 2017, 13, 1932–1939, doi:10.3762/bjoc.13.187

• Göttingen, Germany 10.3762/bjoc.13.187 Abstract A new and efficient approach to five- and six-membered benzannelated sultams by intramolecular C-arylation of tertiary 1-(methoxycarbonyl)methanesulfonamides under palladium catalysis is described. In case of the α-toluenesulfonamide derivative, an unexpected

• formation of a 2,3-diarylindole was observed under the same conditions. Keywords: arylation; fused-ring systems; indole formation; palladium catalysis; sultams; Introduction The sulfonamide functional group stands out as one of the most important pharmacophores. At the same time, cyclic sulfonamides

• (sultams) have also received significant attention due to their biological activities and medicinal uses [1][2][3][4][5][6][7]. On the other hand, especially fused sultams are among the most commonly used therapeutic agents owing to the broad spectrum of their activities [8][9][10][11][12][13]. Up to now

Synthesis of alkynyl-substituted camphor derivatives and their use in the preparation of paclitaxel-related compounds

• M. Fernanda N. N. Carvalho,
• Rudolf Herrmann and
• Gabriele Wagner

Beilstein J. Org. Chem. 2017, 13, 1230–1238, doi:10.3762/bjoc.13.122

• for the synthesis of 12 and 13 introduced the alkyne into the 2-position of the camphor skeleton, to provide the sultams 17. The removal of the acetal-protecting group occurred under comparatively mild conditions by stirring a mixture of 17 with acetone and conc. HCl. Acetone as solvent was best as it

Facile synthesis of benzothiadiazine 1,1-dioxides, a precursor of RSV inhibitors, by tandem amidation/intramolecular aza-Wittig reaction

• Krishna C. Majumdar and
• Sintu Ganai

Beilstein J. Org. Chem. 2013, 9, 503–509, doi:10.3762/bjoc.9.54

• yields and high purity, which is the core moiety of RSV inhibitors. Keywords: benzothiadiazine-3-one 1,1-dioxide; 3-ethoxy-1,2,4-benzothiadiazine 1,1-dioxide; intramolecular aza-Wittig reaction; sultam; Introduction Sultams have gained popularity in the scientific community especially among synthetic

Exploring chemical diversity via a modular reaction pairing strategy

• Joanna K. Loh,
• Sun Young Yoon,
• Thiwanka B. Samarakoon,
• Alan Rolfe,
• Patrick Porubsky,
• Benjamin Neuenswander,
• Gerald H. Lushington and
• Paul R. Hanson

Beilstein J. Org. Chem. 2012, 8, 1293–1302, doi:10.3762/bjoc.8.147

• . Computational analyses were employed to explore and evaluate the chemical diversity of the library. Keywords: benzoxathiazocine 1,1-dioxides; chemical diversity; informatics; nucleophilic aromatic substitution (SNAr); sultams; Introduction The demand for functionally diverse chemical libraries has emerged, as

• hindered these efforts [2][3]. In this regard, recent advances in the construction of chemical libraries that are rich in functional diversity, consisting of appendage, functional group, stereochemical and skeletal diversity, have addressed this challenge and also offer new opportunities [4]. Sultams

• (cyclic sulfonamides) represent a class of compounds with a non-natural chemotype [5][6] that have gained enormous interest in recent years due to their extensive range of biological activities [7][8][9][10][11][12][13][14]. In particular, benzofused sultams, possessing a rich content of sp3 amine

Amines as key building blocks in Pd-assisted multicomponent processes

• Didier Bouyssi,
• Nuno Monteiro and
• Geneviève Balme

Beilstein J. Org. Chem. 2011, 7, 1387–1406, doi:10.3762/bjoc.7.163

• series of benzo-fused sultams. A range of α-bromobenzenesulfonyl chlorides 40 were first coupled with various amines in DMF at room temperature in the presence of Et3N to generate intermediate sulfonamides 41. Subsequent in situ addition of a Michael acceptor in large excess together with Et3N, Bu4NCl

• , and catalytic Pd2(dba)3·CHCl3 led to the production of the desired sultams 42 upon heating at 110 °C. A series of sultam derivatives of bioactive, related isoindol-1-one amides 43 were also prepared by entering acrylic acid into the Heck–aza–Michael process and coupling a second amine derivative

Diastereoselective functionalisation of benzo-annulated bicyclic sultams: Application for the synthesis of cis-2,4-diarylpyrrolidines

• Susan Kelleher,
• Pierre-Yves Quesne and
• Paul Evans

Beilstein J. Org. Chem. 2009, 5, No. 69, doi:10.3762/bjoc.5.69

• Susan Kelleher Pierre-Yves Quesne Paul Evans Centre for Synthesis and Chemical Biology, School of Chemistry and Chemical Biology, University College Dublin, Dublin 4, Ireland 10.3762/bjoc.5.69 Abstract The cis-dibromination of unsaturated bicyclic bridgehead sultams 5a and 5b, and experiments

• demonstrates, in principle, how the trans-2,4-substituted series might also be accessible. The cis-diastereoselective dibromination of the bridgehead sultams 5a and 5b was also studied from a mechanistic perspective and related to this an unusual molecular somersault was uncovered, the occurrence of which was

• -annulated bicyclic sultams: application for the synthesis of cis-2,4-diarylpyrrolidines. Acknowledgments We would like to acknowledge UCD for the provision of a postgraduate scholarship. Additionally Dr. Helge Müller-Bunz is thanked for X-ray crystallography and Dr. Jimmy Muldoon is thanked for assistance