Mechanistic studies of the solvolysis of alkanesulfonyl and arenesulfonyl halides

Malcolm J. D’Souza and
Dennis N. Kevill

Review
Published 17 Jan 2022

PDF
Album
1. Graphical Abstract
2. Scheme 1: Organic reactions where the breaking of a C–X bond involves the formation of a high energy ion-pair...
  
  Jump to Scheme 1
3. Scheme 2: The chemical structures for the 1-adamantyl substrate, 2-adamantyl substrate, and the S-methyldiben...
  
  Jump to Scheme 2
4. Figure 1: The S_N2 reaction plot of log (k/k_o) vs (1.26 N_T + 0.65 Y_Cl) for the solvolyses of benzesulfonyl chl...
  
  Jump to Figure 1
5. Figure 2: The S_N2 reaction plot of log (k/k_o) vs (1.35 N_T + 0.70 Y_Cl) for the solvolyses of 2-thiophenesulfon...
  
  Jump to Figure 2

Beilstein J. Org. Chem. 2022, 18, 120–132, doi:10.3762/bjoc.18.13

Full Text

Tenacibactins K–M, cytotoxic siderophores from a coral-associated gliding bacterium of the genus Tenacibaculum

Yasuhiro Igarashi,
Yiwei Ge,
Tao Zhou,
Amit Raj Sharma,
Enjuro Harunari,
Naoya Oku and
Agus Trianto

Full Research Paper
Published 13 Jan 2022

PDF
Album
1. Graphical Abstract
2. Figure 1: Structures of tenacibactins K–M (1–3).
  
  Jump to Figure 1
3. Figure 2: Key 2D-NMR correlations for 1–3.
  
  Jump to Figure 2
4. Figure 3: (a) Partial ¹H NMR spectra of 1 at 25 and 50 °C in DMSO-d₆; (b) magnified HMBC spectrum of 1 at 25 ...
  
  Jump to Figure 3
5. Figure 4: MS/MS spectrum of 1 acquired on a quadrupole time-of-flight mass spectrometer in the negative ion m...
  
  Jump to Figure 4
6. Scheme 1: MS/MS fragmentation pathway for compound 1.
  
  Jump to Scheme 1
Supp. Info

Beilstein J. Org. Chem. 2022, 18, 110–119, doi:10.3762/bjoc.18.12

Full Text

Regioselective synthesis of methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates as new amino acid-like building blocks

Jolita Bruzgulienė,
Greta Račkauskienė,
Aurimas Bieliauskas,
Vaida Milišiūnaitė,
Miglė Dagilienė,
Gita Matulevičiūtė,
Vytas Martynaitis,
Sonata Krikštolaitytė,
Frank A. Sløk and
Algirdas Šačkus

Full Research Paper
Published 12 Jan 2022

PDF
Album
1. Graphical Abstract
2. Figure 1: Examples of amino-functionalized 1,2-oxazole derivatives I–VIII.
  
  Jump to Figure 1
3. Scheme 1: Conversion of cyclic amino acids to 1,2-oxazole derivatives.
  
  Jump to Scheme 1
4. Scheme 2: Plausible mechanisms for the formation of 1,2-oxazoles 4a–h and VII from β-enamino ketoesters 3a–h ...
  
  Jump to Scheme 2
5. Figure 2: (a) ¹H NMR (italics), ¹³C NMR (normal), and ¹⁵N NMR (bold) chemical shifts (ppm) of compound 3a in ...
  
  Jump to Figure 2
6. Scheme 3: Synthesis of compound ¹⁵N-1,2-oxazole 5. The coupling constants of J_HN and J_CN from ¹⁵N2 are indica...
  
  Jump to Scheme 3
7. Figure 3: Stacked chromatogram view of pairs of enantiomers with area, %: (R)-4b, ee 100% (t_R = 10.1 min) and...
  
  Jump to Figure 3
8. Figure 4: (a) Structure of 4b with syn- and anti-conformers; (b) superimposed ¹H NMR and 1D gradient NOE spec...
  
  Jump to Figure 4
9. Scheme 4: Synthesis of 2-[4-(methoxycarbonyl)-1,2-oxazol-5-yl]cycloaminyl-1-ium trifluoroacetates 6a,b.
  
  Jump to Scheme 4
10. Figure 5: ORTEP diagram of the asymmetric unit consisting of two cations 6b(A) and 6b(B) and triflate anions.
  
  Jump to Figure 5
Supp. Info

Beilstein J. Org. Chem. 2022, 18, 102–109, doi:10.3762/bjoc.18.11

Full Text

Chemical and chemoenzymatic routes to bridged homoarabinofuranosylpyrimidines: Bicyclic AZT analogues

Sandeep Kumar,
Jyotirmoy Maity,
Banty Kumar,
Sumit Kumar and
Ashok K. Prasad

Full Research Paper
Published 11 Jan 2022

PDF
Album
1. Graphical Abstract
2. Figure 1: Structure of AZT and representative related bicyclic nucleosides.
  
  Jump to Figure 1
3. Scheme 1: Retrosynthetic routes for the synthesis of (5′R)-3′-azido-3′-deoxy-2′-O,5′-C-bridged-β-ᴅ-homoarabin...
  
  Jump to Scheme 1
4. Scheme 2: Synthesis of 3′-azido-3′-deoxy-β-ᴅ-allofuranosylthymine (14a) and -uracil (14b).
  
  Jump to Scheme 2
5. Scheme 3: Biocatalytic acetylation of the primary hydroxy group of nucleosides 14a,b.
  
  Jump to Scheme 3
6. Scheme 4: Synthesis of (5'R)-3′-azido-3′-deoxy-2′-O,5′-C-bridged-β-ᴅ-homoarabinofuranosyl nucleosides 9a,b.
  
  Jump to Scheme 4
7. Scheme 5: Chemical synthesis of nucleosides 9a,b starting from diacetone ᴅ-glucofuranose.
  
  Jump to Scheme 5
8. Figure 2: Structure elucidation of (5′R)-3′-azido-3′-deoxy-2′-O,5′-C-bridged-β-ᴅ-homoarabinofuranosylthymine (...
  
  Jump to Figure 2
9. Scheme 6: a) Plausible mechanism for the synthesis of (5′R)-3′-azido-3′-deoxy-2′-O,5′-C-bridged-β-ᴅ-homoarabi...
  
  Jump to Scheme 6
Supp. Info

Beilstein J. Org. Chem. 2022, 18, 95–101, doi:10.3762/bjoc.18.10

Full Text

Chemoselective N-acylation of indoles using thioesters as acyl source

Tianri Du,
Xiangmu Wei,
Honghong Xu,
Xin Zhang,
Ruiru Fang,
Zheng Yuan,
Zhi Liang and
Yahui Li

Full Research Paper
Published 10 Jan 2022

PDF
Album
1. Graphical Abstract
2. Figure 1: Representative pharmaceuticals containing N-acylindole moieties.
  
  Jump to Figure 1
3. Scheme 1: A) Strategies for the synthesis of N-acylindoles; B) thioester as dicarbonylation reagent; C) recen...
  
  Jump to Scheme 1
4. Scheme 2: Reactions of thioesters and indoles. Reaction conditions: 1 (0.2 mmol, 1.0 equiv), 2 (0.6 mmol, 3.0...
  
  Jump to Scheme 2
5. Scheme 3: Gram-scale experiment.
  
  Jump to Scheme 3
6. Scheme 4: Control experiments.
  
  Jump to Scheme 4
7. Scheme 5: Proposed mechanism.
  
  Jump to Scheme 5
Supp. Info

Beilstein J. Org. Chem. 2022, 18, 89–94, doi:10.3762/bjoc.18.9

Full Text

Earth-abundant 3d transition metals on the rise in catalysis

Nikolaos Kaplaneris and
Lutz Ackermann

Editorial
Published 07 Jan 2022

Beilstein J. Org. Chem. 2022, 18, 86–88, doi:10.3762/bjoc.18.8

Full Text

Efficient and regioselective synthesis of dihydroxy-substituted 2-aminocyclooctane-1-carboxylic acid and its bicyclic derivatives

İlknur Polat,
Selçuk Eşsiz,
Uğur Bozkaya and
Emine Salamci

Full Research Paper
Published 06 Jan 2022

PDF
Album
1. Graphical Abstract
2. Figure 1: Examples of natural products containing β-amino acids.
  
  Jump to Figure 1
3. Scheme 1: Synthesis of cyclic β-amino acid 6.
  
  Jump to Scheme 1
4. Scheme 2: Epoxidation of Boc-protected amino ester 4 and hydrolysis of epoxide 7 with HCl(g)–MeOH.
  
  Jump to Scheme 2
5. Scheme 3: Reaction of epoxide 7 with NaHSO₄ in methylene chloride/MeOH.
  
  Jump to Scheme 3
6. Figure 2: The X-ray crystal structure of 10.
  
  Jump to Figure 2
7. Scheme 4: Synthesis of cyclic β-amino acid derivative 8.
  
  Jump to Scheme 4
8. Scheme 5: Suggested mechanism for the reaction of epoxide 7 with NaHSO₄.
  
  Jump to Scheme 5
9. Figure 3: Solvent-corrected relative free energy profile at 298.15 K for the reaction mechanism of 14 shown i...
  
  Jump to Figure 3
10. Figure 4: Solvent-corrected relative free energy profile at 298.15 K for the reaction mechanism of 17 shown i...
  
  Jump to Figure 4
11. Figure 5: The optimized geometries of the conformers 7a and 7b with selected interatomic distances at the B3L...
  
  Jump to Figure 5
Supp. Info

Beilstein J. Org. Chem. 2022, 18, 77–85, doi:10.3762/bjoc.18.7

Full Text

Efficient synthesis of ethyl 2-(oxazolin-2-yl)alkanoates via ethoxycarbonylketene-induced electrophilic ring expansion of aziridines

Yelong Lei and
Jiaxi Xu

Full Research Paper
Published 05 Jan 2022

PDF
Album
1. Graphical Abstract
2. Figure 1: Oxazoline-containing bioactive natural products.
  
  Jump to Figure 1
3. Scheme 1: Synthetic methods of oxazoline derivatives.
  
  Jump to Scheme 1
4. Scheme 2: Scopes of aziridines and diazo esters.
  
  Jump to Scheme 2
5. Scheme 3: Proposed reaction mechanism.
  
  Jump to Scheme 3
6. Scheme 4: Direction of tautomerization.
  
  Jump to Scheme 4
Supp. Info

Beilstein J. Org. Chem. 2022, 18, 70–76, doi:10.3762/bjoc.18.6

Full Text

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

Ruan Carlos B. Ribeiro,
Patricia G. Ferreira,
Amanda de A. Borges,
Luana da S. M. Forezi,
Fernando de Carvalho da Silva and
Vitor F. Ferreira

Review
Published 05 Jan 2022

PDF
Album
1. Graphical Abstract
2. Figure 1: Naphthoquinones are commonly used in organic synthesis.
  
  Jump to Figure 1
3. Figure 2: Some important natural and synthetic naphthoquinones.
  
  Jump to Figure 2
4. Scheme 1: Synthetic studies of BNQs and reactions with amines.
  
  Jump to Scheme 1
5. Scheme 2: Methods described for the synthesis of β-NQS.
  
  Jump to Scheme 2
6. Figure 3: Drugs detected using β-NQSNa.
  
  Jump to Figure 3
7. Scheme 3: Reactions between β-NQS and amines.
  
  Jump to Scheme 3
8. Scheme 4: Isomerization of 4-arylamino-1,2-naphthoquinones.
  
  Jump to Scheme 4
9. Scheme 5: Synthesis of unsymmetrical 2-amino-4-imino compounds.
  
  Jump to Scheme 5
10. Scheme 6: Synthesis of bis(isoxazolyl)naphthoquinones from β-NQS.
  
  Jump to Scheme 6
11. Scheme 7: The reaction of β-NQS with 30 followed by cycle condensation.
  
  Jump to Scheme 7
12. Scheme 8: Synthesis of 4-(2-amino-5-selenothiazoles)-1,2-naphthoquinones.
  
  Jump to Scheme 8
13. Scheme 9: Synthesis of amino- and phenoxy-1,2-naphthoquinones.
  
  Jump to Scheme 9
14. Scheme 10: Synthesis of 4-semicarbazide-1,2-naphthoquinone.
  
  Jump to Scheme 10
15. Scheme 11: Reactions of 4-azido-1,2-naphthoquinone.
  
  Jump to Scheme 11
16. Figure 4: Modifications that can be easily carried out from the products of β-NQS 8.
  
  Jump to Figure 4
17. Scheme 12: Derivatives of 1,2-naphthoquinones obtained from β-NQS.
  
  Jump to Scheme 12
18. Scheme 13: Oximes as well as 4-amino- and 4-phenoxy-1,2-naphthoquinone as potential anti-inflammatory agents.
  
  Jump to Scheme 13
19. Scheme 14: Synthesis of triazoles from β-NQS.
  
  Jump to Scheme 14
20. Scheme 15: Synthesis of naphtho[1,2-d]oxazoles from β-NQS.
  
  Jump to Scheme 15
21. Scheme 16: A) Arylation and vinylation of β-NQS catalyzed by Ni(II) salts. B) Transformation of the 1,2-dicarb...
  
  Jump to Scheme 16
22. Scheme 17: Benzo[a]carbazole and benzo[c]carbazoles fused with 1,2-naphthoquinone.
  
  Jump to Scheme 17
23. Scheme 18: Synthesis of 1,2-naphthoquinones having a C=C bond from β-NQS. Method A: NaOH, EtOH/H₂O, 40 °C, 2 h...
  
  Jump to Scheme 18
24. Scheme 19: C=C bond formation from β-NQS and substituted acetonitriles.
  
  Jump to Scheme 19

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

Full Text

Recent advances and perspectives in ruthenium-catalyzed cyanation reactions

Thaipparambil Aneeja,
Cheriya Mukkolakkal Abdulla Afsina,
Padinjare Veetil Saranya and
Gopinathan Anilkumar

Review
Published 04 Jan 2022

PDF
Album
1. Graphical Abstract
2. Scheme 1: Starch-immobilized ruthenium trichloride-catalyzed cyanation of tertiary amines.
  
  Jump to Scheme 1
3. Scheme 2: Proposed mechanism for the cyanation of tertiary amines using starch-immobilized ruthenium trichlor...
  
  Jump to Scheme 2
4. Scheme 3: Cyanation of tertiary amines using heterogeneous Ru/C catalyst.
  
  Jump to Scheme 3
5. Scheme 4: Proposed mechanism for cyanation of tertiary amines using a heterogeneous Ru/C catalyst.
  
  Jump to Scheme 4
6. Scheme 5: Ruthenium-carbamato complex-catalyzed oxidative cyanation of tertiary amines.
  
  Jump to Scheme 5
7. Scheme 6: Cyanation of tertiary amines using immobilized MCM-41-2N-RuCl₃ as the catalyst.
  
  Jump to Scheme 6
8. Scheme 7: Cyanation of tertiary amines using RuCl₃·nH₂O as the catalyst and molecular oxygen as oxidant.
  
  Jump to Scheme 7
9. Scheme 8: RuCl₃-catalyzed cyanation of tertiary amines using NaCN/HCN and H₂O₂ as oxidant.
  
  Jump to Scheme 8
10. Scheme 9: Proposed mechanism for the ruthenium-catalyzed oxidative cyanation using H₂O₂.
  
  Jump to Scheme 9
11. Scheme 10: Proposed mechanism for the ruthenium-catalyzed aerobic oxidative cyanation.
  
  Jump to Scheme 10
12. Scheme 11: RuCl₃-catalyzed oxidative cyanation of tertiary amines using acetone cyanohydrin as the cyanating a...
  
  Jump to Scheme 11
13. Scheme 12: Cyanation of indoles using K₄[Fe(CN)₆] as cyano source and Ru(III)-exchanged NaY zeolite (RuY) as c...
  
  Jump to Scheme 12
14. Scheme 13: Cyanation of arenes and heteroarenes using a ruthenium(II) catalyst and N-cyano-N-phenyl-p-toluenes...
  
  Jump to Scheme 13
15. Scheme 14: Proposed mechanism for the cyanation of arenes and heteroarenes using ruthenium(II) as catalyst and...
  
  Jump to Scheme 14
16. Scheme 15: Synthesis of N-(2-cyanoaryl)-7-azaindoles.
  
  Jump to Scheme 15
17. Figure 1: Structure of the TiO₂-immobilized ruthenium polyazine complex.
  
  Jump to Figure 1
18. Scheme 16: Visible-light-induced oxidative cyanation of aza-Baylis–Hillman adducts.
  
  Jump to Scheme 16
19. Scheme 17: Synthesis of 1° alkyl nitriles using [Ru(bpy)₃](PF₆)₂ as the photocatalyst.
  
  Jump to Scheme 17
20. Scheme 18: Synthesis of 2° and 3° alkyl nitriles using [Ru(bpy)₃](PF₆)₂ as the photocatalyst.
  
  Jump to Scheme 18
21. Scheme 19: Photoredox cross coupling reaction.
  
  Jump to Scheme 19
22. Scheme 20: Synthesis of α-amino nitriles from amines via a one-pot strategy.
  
  Jump to Scheme 20
23. Scheme 21: Proposed mechanistic pathway for the cyanation of the aldimine intermediate.
  
  Jump to Scheme 21
24. Scheme 22: Strecker-type functionalization of N-aryl-substituted tetrahydroisoquinolines under flow conditions....
  
  Jump to Scheme 22
25. Scheme 23: One-pot synthesis of α-aminonitriles using RuCl₃ as catalyst.
  
  Jump to Scheme 23
26. Scheme 24: Synthesis of alkyl nitriles using (Ru(TMHD)₃) as the catalyst.
  
  Jump to Scheme 24
27. Scheme 25: Synthesis of cyanated isoxazolines from alkenyl oximes catalyzed by [RuCl₂(p-cymene)]₂ in the prese...
  
  Jump to Scheme 25
28. Scheme 26: Proposed mechanism for the synthesis of cyanated isoxazolines from alkenyl oximes.
  
  Jump to Scheme 26
29. Scheme 27: Oxidative cyanation of differently substituted alcohols.
  
  Jump to Scheme 27