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1. One-Pot Conversion of Aldehydes and Aryl Halides to Disubstituted Alkynes via Tandem Seyferth–Gilbert Homologation/Copper-Free Sonogashira Coupling

Author:
Krasavin, Mikhail,   et al.   ; Sapegin, Alexander;     Show all 2 Author
Source:
Journal of organic chemistry 2019 v.84 no.13 pp. 8788-8795
ISSN:
1520-6904
Subject:
acetylene; aldehydes; catalysts; chemical reactions; chemical structure; copper; organic chemistry; organic halogen compounds; palladium
Abstract:
... A practically convenient protocol has been developed to convert a mixture of an aldehyde, aryl halide, and the Bestmann–Ohira reagent into disubstituted acetylene via a successive addition of base (Cs₂CO₃) and a Pd(II) catalyst, allowing sufficient time after addition of each of these reagents for the tandem processes (Seyferth–Gilbert homologation and Sonogashira coupling) to occur. Notably, for ...
DOI:
10.1021/acs.joc.9b01367

2. A novel variant of the medicinally relevant 1,2,5-benzothiadiazepin-4-one-1,1-dioxide scaffold accessed via the downstream modification of Castagnoli-Cushman lactams

Author:
Krasavin, Mikhail,   et al.   ; Usmanova, Liliia; Dar'in, Dmitry;     Show all 3 Authors
Source:
Tetrahedron letters 2019
ISSN:
0040-4039
Subject:
X-ray diffraction; chemical reactions; chemical structure; lactams; spectral analysis; stereochemistry
Abstract:
... Downstream modification of piperazin-2-ones obtained by the Castagnoli-Cushman reaction leads to a novel version of the medicinally relevant 1,2,5-benzothiadiazepin-4-one-1,1-dioxide scaffold. The relative stereochemistry remained trans as evidenced by the spectroscopic data and the single-crystal X-ray analysis. ...
DOI:
10.1016/j.tetlet.2019.151003

3. “Isocyanide-less” Ugi/Intramolecular Diels-Alder reaction of 5-hydroxymethylfurfural

Author:
Krasavin, Mikhail,   et al.   ; Golubev, Pavel; Pankova, Alena;     Show all 3 Authors
Source:
Tetrahedron letters 2019 v.60 no.24 pp. 1578-1581
ISSN:
0040-4039
Subject:
chemical structure; cycloaddition reactions; diastereoselectivity; hydroxymethylfurfural; stereospecificity
Abstract:
... The one-pot, three-step, four-component Ugi-IMDAF reaction with 5-hydroxymethylfurfural provides simple access to hydroxymethyl-substituted epoxyisoindolones in a diastereoselective and stereospecific manner. The protocol avoids the transfer or isolation of isocyanides, and the broad scope was illustrated by the synthesis of 22 different compounds bearing various substituents on the heterocyclic c ...
DOI:
10.1016/j.tetlet.2019.05.018

4. A ‘sulfonyl-azide-free’ (SAFE) aqueous-phase diazo transfer reaction for parallel and diversity-oriented synthesis

Author:
Krasavin, Mikhail,   et al.   ; Dar’in, Dmitry; Kantin, Grigory;     Show all 3 Authors
Source:
Chemical communications 2019 v.55 no.36 pp. 5239-5242
ISSN:
1364-548X
Subject:
azides; chemical reactions; diazo compounds
Abstract:
... Diazo transfer reactions are notoriously associated with the use of potentially explosive sulfonyl azides. The first ‘sulfonyl-azide-free’ (SAFE) protocol for producing diazo compounds from their active-methylene precursors via the Regitz diazo transfer reaction was developed and has displayed a remarkable substrate scope. It can be applied to generating arrays of diazo compounds for further evolu ...
DOI:
10.1039/c9cc02042j

5. N-Isocyanodialkylamines generated in situ for the Joullié–Ugi reaction with indolenines

Author:
Krasavin, Mikhail,   et al.   ; Golubev, Pavel;     Show all 2 Author
Source:
Tetrahedron letters 2018 v.59 no.39 pp. 3532-3536
ISSN:
0040-4039
Subject:
acetic acid; chemical reactions; chemical structure; hydrazines; protocols; smell
Abstract:
... N-Isocyanodialkylamines are rare isocyanide surrogates for the Ugi-type reactions. To avoid problems with instability and the obnoxious smell of these reagents, we optimized and employed a convenient protocol for in situ dehydration of N,N-dialkyl-N′-formyl hydrazines to give the respective N-isocyanodialkylamines which were utilized in the reaction with indolenines and acetic acid. The reaction w ...
DOI:
10.1016/j.tetlet.2018.08.025

6. Efficient Suzuki-Miyaura mono-arylation of symmetrical diiodo(hetero)arenes

Author:
Krasavin, Mikhail,   et al.   ; Sapegin, Alexander;     Show all 2 Author
Source:
Tetrahedron letters 2018 v.59 pp. 1948-1951
ISSN:
0040-4039
Subject:
aromatic hydrocarbons; chemical reactions; chemical structure
Abstract:
... A reliable protocol for converting 1,4-diiodo-2,3,5,6-tetrafluorobenzene into 1-(hetero)aryl-4-iodo-2,3,5,6-tetrafluorobenzene derivatives has been lacking in the literature. We have identified optimal conditions to achieve this conversion in good yields and have minimized formation of the bis-coupling product. The newly identified protocol involving the use of a syringe pump has been extended to ...
DOI:
10.1016/j.tetlet.2018.04.015

7. Three-Component Castagnoli–Cushman Reaction of 3-Arylglutaconic Acids with Aromatic Aldehydes and Amines Delivers Rare 4,6-Diaryl-1,6-dihydropyridin-2(3H)-ones

Author:
Krasavin, Mikhail,   et al.   ; Firsov, Andrei; Chupakhin, Evgeny; Dar’in, Dmitry; Bakulina, Olga;     Show all 5 Authors
Source:
Organic letters 2019 v.21 no.6 pp. 1637-1640
ISSN:
1523-7052
Subject:
acids; aldehydes; amines; bioactive compounds; chemical structure; chemotypes; heterocyclic compounds; isomerization; stereoselectivity
Abstract:
... Attempted use of 3-arylglutaconic acids in the three-component version of the Castagnoli–Cushman reaction with amines and aromatic aldehydes resulted in an unexpected formation of 4,6-diaryl 1,6-dihydropyridine-2(3H)-ones. These are of interest as representatives of a rare heterocyclic chemotype for de novo biological investigation. Alternatively, these compounds can be oxidized into their 2-pyrid ...
DOI:
10.1021/acs.orglett.9b00171

8. Antiviral drug nevirapine as a template for hydrated imidazoline ring expansion (HIRE): Rapid access to the diarene-fused 1,4,7-triazecine ring system

Author:
Krasavin, Mikhail,   et al.   ; Grintsevich, Sergey; Sapegin, Alexander; Reutskaya, Elena;     Show all 4 Authors
Source:
Tetrahedron letters 2019 v.60 no.1 pp. 20-22
ISSN:
0040-4039
Subject:
alkylation; antiviral agents; lactams; moieties; nitrogen
Abstract:
... The tricyclic ring system of the antiviral drug nevirapine has been employed to test the workability of the hydrated imidazoline ring expansion (HIRE) reaction which was previously exemplified for [1.4]oxazepine and [1.4]thiazepine counterparts. The imidazoline nucleus was grafted onto the lactam moiety of nevirapine in two high-yielding steps. Subsequent N-alkylation and the HIRE reaction proceed ...
DOI:
10.1016/j.tetlet.2018.11.044

9. The use of ∝-diazo-γ-butyrolactone in the Büchner-Curtius-Schlotterbeck reaction of cyclic ketones: A facile entry into spirocyclic scaffolds

Author:
Krasavin, Mikhail,   et al.   ; Shershnev, Ivan; Dar'in, Dmitry; Chuprun, Sergey; Kantin, Grigory; Bakulina, Olga;     Show all 6 Authors
Source:
Tetrahedron letters 2019 v.60 no.27 pp. 1800-1802
ISSN:
0040-4039
Subject:
catalysts; chemical reactions; chemical structure; diazo compounds; ketones
Abstract:
... The first example of the Büchner-Curtius-Schlotterbeck reaction of cyclic ketones with a stabilized cyclic diazo compound partner is described. The approach towards spirocyclic scaffolds has been exemplified with readily available ∝-diazo-γ-butyrolactone. The reaction proved to be viable with BF3∙OEt2 as the preferred catalyst and displayed substantial sensitivity to the size of the cyclic ketone. ...
DOI:
10.1016/j.tetlet.2019.06.008

10. Fused vs. spiro: Kinetic, not thermodynamic preference may direct the reaction of α-carbonyl oxonium ylides

Author:
Krasavin, Mikhail,   et al.   ; Guranova, Natalia I.; Dar'in, Dmitry; Kantin, Grigory; Novikov, Alexander S.; Bakulina, Olga;     Show all 6 Authors
Source:
Tetrahedron letters 2019 v.60 no.24 pp. 1582-1586
ISSN:
0040-4039
Subject:
chemical reactions; chemical structure; cyclic ethers; oxygen; quantum mechanics; thermodynamics
Abstract:
... Rh(II)-catalyzed decomposition of certain cyclic α-diazocarbonyl compounds in the presence of cyclic ethers has been shown to give bicyclic ring expansion products. These are thought to arise from a [1,4]-alkyl shift toward the carbonyl oxygen atom and are in contrast with the recently observed spirocyclic products of a Stevens-type [1,2]-alkyl shift within the postulated oxonium ylide intermediat ...
DOI:
10.1016/j.tetlet.2019.05.020

11. Zn(OTf)2-catalyzed, microwave-promoted synthesis of 2-substituted 5-methyloxazoles from propargylic amides

Author:
Krasavin, Mikhail,   et al.   ; Safrygin, Alexander; Dar'in, Dmitry; Lukin, Alexei; Bakholdina, Anna; Sapegin, Alexander;     Show all 6 Authors
Source:
Tetrahedron letters 2019 v.60 no.11 pp. 777-779
ISSN:
0040-4039
Subject:
amides; chemical reactions; chemical structure; heterocyclic compounds; microwave radiation; toluene; zinc
Abstract:
... The versatile conversion of propargylic amides to the respective 2-substituted 5-methyloxazoles was efficiently catalyzed by Zn(OTf)2 (5 mol%) under microwave irradiation in toluene. The method was applicable to a wide range of aliphatic, aromatic and heteroaromatic propargylic amides and thus represents a useful method which is complementary to the existing metal-catalyzed protocols, considering ...
DOI:
10.1016/j.tetlet.2019.02.011

12. Rh(II)-Catalyzed Spirocyclization of α-Diazo Homophthalimides with Cyclic Ethers

Author:
Krasavin, Mikhail,   et al.   ; Guranova, Natalia I.; Dar’in, Dmitry; Kantin, Grigory; Novikov, Alexander S.; Bakulina, Olga;     Show all 6 Authors
Source:
Journal of organic chemistry 2019 v.84 no.7 pp. 4534-4542
ISSN:
1520-6904
Subject:
chemical reactions; chemical structure; cyclic ethers; organic chemistry; prediction; quantum mechanics; thermodynamics
Abstract:
... Rh(II)-catalyzed decomposition of α-diazo homophthalimides in the presence of cyclic ethers gave spirocyclic products of Stevens-type [1,2]-alkyl shift within the postulated oxonium ylide intermediate. Such a reaction pathway is in line with thermodynamic predictions obtained from quantum chemical calculations performed at the B3LYP/6-31G* and B3LYP/6-311++G** levels of theory. These findings repr ...
DOI:
10.1021/acs.joc.9b00245

13. Synthesis of various arylated trifluoromethyl substituted indanes and indenes, and study of their biological activity

Author:
Krasavin, Mikhail,   et al.   ; Iakovenko, Roman O.; Chicca, Andrea; Nieri, Daniela; Reynoso-Moreno, Ines; Gertsch, Jürg; Vasilyev, Aleksander V.;     Show all 7 Authors
Source:
Tetrahedron 2019 v.75 no.5 pp. 624-632
ISSN:
0040-4020
Subject:
Lewis acids; acylglycerol lipase; alcohols; amide hydrolases; arylation; bioactive properties; cannabinoids; fatty acids; humans; indenes; lipophilicity; moieties; receptors
Abstract:
... A series of 1-trifluoromethyl substituted indanes and indenes bearing aryl groups in positions 1 and/or 3 of the indane core have been synthesized mainly by electrophilic cyclization and arylation of the corresponding trifluoromethylated allyl and propargyl alcohols. The distinctly lipophilic compounds thus obtained were tested against various components of human endocannabinoid system. None of th ...
DOI:
10.1016/j.tet.2018.12.041

14. Unusually Reactive Cyclic Anhydride Expands the Scope of the Castagnoli–Cushman Reaction

Author:
Krasavin, Mikhail,   et al.   ; Chizhova, Maria; Khoroshilova, Olesya; Dar’in, Dmitry;     Show all 4 Authors
Source:
Journal of organic chemistry 2018 v.83 no.20 pp. 12722-12733
ISSN:
1520-6904
Subject:
anhydrides; chemical reactions; chemical structure; enols; imines; organic chemistry
Abstract:
... In the course of synthesizing and testing various “azole-including” cyclic anhydrides in the Castagnoli–Cushman reaction with imines, a remarkably reactive, pyrrole-based anhydride has been identified. It displayed a remarkably efficient reaction with N-alkyl and N-aryl imines, in particular, with “enolizable” α-C-H imines which typically fail to react with a majority of known cyclic anhydrides. T ...
DOI:
10.1021/acs.joc.8b02164

15. Rare Medium-Sized Rings Prepared via Hydrolytic Imidazoline Ring Expansion (HIRE)

Author:
Krasavin, Mikhail,   et al.   ; Osipyan, Angelina; Sapegin, Alexander; Novikov, Alexander S.;     Show all 4 Authors
Source:
Journal of organic chemistry 2018 v.83 no.17 pp. 9707-9717
ISSN:
1520-6904
Subject:
bioactive compounds; chemical reactions; chemical structure; organic chemistry; organic compounds
Abstract:
... The hydrolytic imidazoline ring expansion (HIRE) methodology was extended to readily available tetracyclic [1,4]thiazepines as well as sulfoxide and sulfone analogs thereof. The reactions resulted in the facile formation of a rare medium-sized [1,4,7]thiazecine ring system that has an emerging utility in bioactive compound design. Comparing the HIRE rates for representative compounds in the three ...
DOI:
10.1021/acs.joc.8b01210

16. Diversity-oriented synthesis of N,N-dimethylamino-substituted azoles employing TBTU

Author:
Krasavin, Mikhail,   et al.   ; Lukin, Alexey; Kalinchenkova, Natalya; Vedekhina, Tatiana; Zhurilo, Nikolay;     Show all 5 Authors
Source:
Tetrahedron letters 2018 v.59 pp. 2732-2735
ISSN:
0040-4039
Subject:
azoles; chemical reactions; chemical structure; hydrazines
Abstract:
... A convenient, diversity-oriented approach for the transformation of readily available amidoximes, o-hydroxyarylamines, acyl hydrazines, carboximidohydrazides and thiohydrazides into their respective N,N-dimethylamino-substituted azoles is described. The method is particularly suitable for array chemistry application as it employs a stable, solid reagent TBTU. ...
DOI:
10.1016/j.tetlet.2018.05.075

17. Concise synthesis of 2-N-hydroxy-3,4-dihydroisoquinol-2-one: A bacterial siderophore and human 5-lipooxygenase inhibitor

Author:
Krasavin, Mikhail,   et al.   ; Tutov, Anna; Bakulina, Olga; Dar'in, Dmitry;     Show all 4 Authors
Source:
Tetrahedron letters 2018 v.59 no.15 pp. 1511-1512
ISSN:
0040-4039
Subject:
chemical reactions; chemical structure; enzyme inhibitors; humans; organic compounds; siderophores
Abstract:
... A short synthesis of 2-N-hydroxy-3,4-dihydroisoquinol-2-one has been devised, which is based on the Castagnoli-Cushman reaction and 3 times more high-yielding compared to an earlier reported sequence. ...
DOI:
10.1016/j.tetlet.2018.03.017

18. Acetic anhydride to the rescue: Facile access to privileged 1,2,3,4-tetrahydropyrazino[1,2-a]indole core via the Castagnoli-Cushman reaction

Author:
Krasavin, Mikhail,   et al.   ; Chizhova, Maria; Khoroshilova, Olesya; Dar'in, Dmitry;     Show all 4 Authors
Source:
Tetrahedron letters 2018
ISSN:
0040-4039
Subject:
acetic anhydride; chemical reactions; chemical structure; dicarboxylic acids; imines
Abstract:
... Indole-fused cyclic anhydrides earlier deemed unreactive in the Castagnoli-Cushman reaction with imines have been rendered valid participant in this process. The new reaction format involves the use of respective indole-based dicarboxylic acids and in situ cyclodehydration of the latter by acetic anhydride. This finding validates a fundamentally new approach to synthesizing compounds based on the ...
DOI:
10.1016/j.tetlet.2018.08.049

19. Biocompatible zinc(II) 8-(dihydroimidazolyl)quinoline complex and its catalytic application for synthesis of poly(L,L-lactide)

Author:
Krasavin, Mikhail,   et al.   ; Bolotin, Dmitrii S.; Korzhikov-Vlakh, Viktor; Sinitsyna, Ekaterina; Yunusova, Sevilya N.; Suslonov, Vitalii V.; Shetnev, Anton; Osipyan, Angelina; Kukushkin, Vadim Yu.;     Show all 9 Authors
Source:
Journal of catalysis 2019 v.372 pp. 362-369
ISSN:
0021-9517
Subject:
Lewis bases; catalysts; catalytic activity; composite polymers; drugs; ethyl acetate; intravenous injection; methanol; nanospheres; particle size distribution; polymerization; quinoline; toxicity; zinc
Abstract:
... A 1:1 reaction of 8-(dihydroimidazolyl)quinoline (abbreviated as L) with MCl2·2H2O (M = CoII, NiII, CuII, ZnII) conducted in EtOAc (for ZnII and CuII) or MeOH (NiII and CoII) at 50 °C for 10 min provided the respective air- and shelf-stable [MCl2L] complexes (94–96%). The catalytic activity of these well-defined species was evaluated in L-lactide ring-opening polymerization (ROP) that was conducte ...
DOI:
10.1016/j.jcat.2019.03.002

20. The Chan–Evans–Lam N-Arylation of 2-Imidazolines

Author:
Krasavin, Mikhail,   et al.   ; Dar’in, Dmitry;     Show all 2 Author
Source:
Journal of organic chemistry 2016 v.81 no.24 pp. 12514-12519
ISSN:
1520-6904
Subject:
acetates; acids; ambient temperature; chemical reactions; chemical structure; copper; dimethyl sulfoxide; halides; organic chemistry
Abstract:
... N-Arylation of 2-imidazolines with arylboronic acids promoted by copper(II) acetate in DMSO provides an attractive alternative to the earlier reported transition metal-catalyzed approaches employing (hetero)aryl halides as it taps into the vast reagent space of commercially available boronic acids and proceeds at ambient temperature. Many of the resulting compounds are distinctly lead-like, thus p ...
DOI:
10.1021/acs.joc.6b02404