HPLC-free Protein Synthesis

HPLC-free Protein Synthesis

First methode for the fast chemical total synthesis of proteins without HPLC-purification

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Water and n-Butyllithium Together At Last

Water and n-Butyllithium Together At Last

Cycloaddition of nitrone ylides with aldehydes using catalytic amounts of nBuLi

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Improved Catalyst for Hydrogen Production

Improved Catalyst for Hydrogen Production

Engineering water dissociation sites by doping molybdenum disulfide

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A Milder Way to SCF3 Incorporation

A Milder Way to SCF₃ Incorporation

Perfluoroalkylthiolation of alkynes under mild, base-free conditions

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Ethyl 2-(3-chloro-5-cyanophenoxy)acetate

Molecular Formula:	C11H10ClNO3
Molecular Weight:	239.655 g/mol

COSY PREDICT

Ethyl 2-(3-chloro-5-cyanophenoxy)acetate

Characterization Data:

1H NMR (CDCl3, 500 MHz) δ 7.29 (m, 1H), 7.15 (m, 1H), 7.06 (m, 1H), 4.67 (s, 2H), 4.32 (q, J = 7.0 Hz, 2H), 1.35 (t, J = 7 Hz, 3H).

13C NMR (CDCl3, 125 MHz) δ = 167.5,158.6, 136.2, 125.2, 120.3, 117.2, 116.4, 114.4, 65.5, 61.8, 14.1 ppm.

HRMS (ESI) cald for C11H11NO3Cl [M+H]+240.0427, found 240.0418. 

Melting point: 41-42 °C.




1H NMR (CDCl3, 500 MHz) δ 7.29 (m, 1H), 7.15 (m, 1H), 7.06 (m, 1H), 4.67 (s, 2H), 4.32 (q, J = 7.0 Hz, 2H), 1.35 (t, J = 7 Hz, 3H).
below

13C NMR (CDCl3, 125 MHz) δ = 167.5,158.6, 136.2, 125.2, 120.3, 117.2, 116.4, 114.4, 65.5, 61.8, 14.1 ppm.
above


1H NMR predict

13 C NMR PREDICT

HSQC PREDICT

////////////////////
Clc1cc(cc(OCC(=O)OCC)c1)C#N

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

.

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

Mohammad Haji

Beilstein J. Org. Chem. 2016, 12, 1269–1301. published 21 Jun 2016

 

Chemistry Department, Science and Research Branch, Islamic Azad University, Tehran, Iran

 Corresponding author email     mh_1395@yahoo.com

Associate Editor: T. J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 1269–1301.

doi:10.3762/bjoc.12.121

Abstract

Multicomponent reactions (MCRs) are one of the most important processes for the preparation of highly functionalized organic compounds in modern synthetic chemistry. As shown in this review, they play an important role in organophosphorus chemistry where phosphorus reagents are used as substrates for the synthesis of a wide range of phosphorylated heterocycles. In this article, an overview about multicomponent reactions used for the synthesis of heterocyclic compounds bearing a phosphonate group on the ring is given.

http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-12-121&vt=f&tpn=0&bpn=home

Conclusion

In this article the use of different multicomponent reactions (MCRs) for the synthesis of heterocyclic phosphonates has been reviewed. This review demonstrates the synthetic potential of multicomponent reactions for the construction of phosphono-substituted heterocyclic rings. The Kabachnik–Fields reaction can be considered the starting point of multicomponent synthesis of this class of compounds. However, the major advancements in this interesting field have been achieved in recent years. More than 75% of the cited literature in this review has been published within the last six years, of which more than three quarters dealt with the synthesis of new heterocyclic phosphonates from non-heterocyclic phosphorus reagents. The remaining works reported the phosphorylation of parent heterocyclic systems. It is worth mentioning, that most of the cited publications focused on the synthesis of five and six-membered rings and only four articles described the synthesis of three and seven-membered heterocycles. Additionally, the majority of the reported syntheses were devoted to the development of new methodologies including the use of advanced catalytic systems, alternative solvents and microwave irradiation. Thus, the development of novel MCR based on phosphorous reagents would allow the synthesis of macrocyclic and medium or large-sized heterocyclic systems, substances which are currently underrepresented in the literature. Further, the design of new biocompatible scaffolds such as β-lactams and peptidomimetics possessing phosphonate groups by MCR-based strategies would significantly extend the synthetic potential of MCRs towards heterocyclic phosphonates

//////////multicomponent reactions,  organophosphorus chemistry,  phosphorus reagents,  phosphorylated heterocycles

Nickel-Catalyzed Decarbonylative Suzuki–Miyaura Coupling of Amides To Generate Biaryls

Shi et al. have reported a nickel-catalyzed decarbonylative Suzuki–Miyaura reaction which uses an N-aroylpiperidine-2,6-dione as the coupling partner for the boronic acid ( Angew. Chem., Int. Ed. 2016, 55, 6959−6963).

The method is attractive from the point of view of the stability of N-aroylpyrrolidine-2,5-diones toward storage and manipulation and the flexibility they add to the chemist’s toolbox, given their preparation from a different group of precursors to aryl halides or triflates.

Notably, the reaction uses an air-stable and inexpensive nickel catalyst, and the reactions tolerate the presence of water. While a standard reaction temperature of 150 °C is quoted, the use of temperatures as low as 80 °C also seem to be possible. Coupling efficiency is reported to be adversely affected when the aromatic rings of both of the coupling partners bear electron-donating substituents.

Ortho substituents on the aromatic rings seem to be beneficial as they facilitate decarbonylation as part of the cross-coupling. Oxidative addition into the N–C(aroyl) bond of the amide is proposed as initiating the catalytic cycle and is possible on account of a reduction in the resonance stabilization of the N-aroyl functionality versus a conventional aromatic amide.

Suzuki–Miyaura Coupling

Synthesis of Biaryls through Nickel-Catalyzed Suzuki–Miyaura Coupling of Amides by Carbon–Nitrogen Bond Cleavage (pages 6959–6963)Shicheng Shi, Guangrong Meng and Prof. Dr. Michal Szostak
Version of Record online: 21 APR 2016 | DOI: 10.1002/anie.201601914

Breaking and making: The first nickel-catalyzed Suzuki–Miyaura coupling of amides for the synthesis of biaryl compounds through N−C amide bond cleavage is reported. The reaction tolerates a wide range of sensitive and electronically diverse substituents on both coupling partners.

1H NMR (500 MHz, CDCl3) δ 7.70 (s, 4 H), 7.61 (d, J = 7.3 Hz, 2 H), 7.48 (t, J = 7.6 Hz, 2 H), 7.42 (t, J = 7.3 Hz, 1 H).


13C NMR (125 MHz, CDCl3) δ 144.87, 139.92, 129.48 (q, J F = 32.5 Hz), 129.13, 128.32, 127.56, 127.42, 125.83 (q, J F = 3.8 Hz), 124.46 (q, J F = 270.0 Hz).

19F NMR (471 MHz, CDCl3) δ -62.39.

Michal Szostakemail: michal.szostak@rutgers.edu office: Olson 204 E-mail address:michal.szostak@rutgers.edu ORCID:orcid.org/0000-0002-9650-9690 Department of Chemistry, Rutgers University, Newark, NJ, USA

Research Interests

The central theme of our research is synthetic organic and organometallic chemistry with a focus on the development of new synthetic methods based on transition metal catalysis and various aspects of transition metal mediated free radical chemistry and their application to the synthesis of biologically active molecules.

Selected Publications

1. Graphene-Catalyzed Direct Friedel-Crafts Alkylation Reactions: Mechanism, Selectivity and Synthetic Utility. Hu, F.; Patel, M.; Luo, F.; Flach, C.; Mendelsohn, R.; Garfunkel, E.; He, H.; Szostak, M. J. Am. Chem. Soc. 2015, 137 [doi]
2. General Olefin Synthesis by the Palladium-Catalyzed Heck Reaction of Amides: Sterically-Controlled Chemoselective N-C Activation. Meng, G.; Szostak, M. Angew. Chem. Int. Ed. 2015, 54[doi]
3. Aminoketyl Radicals in Organic Synthesis: Stereoselective Cyclization of 5- and 6-Membered Cyclic Imides to 2-Azabicycles using SmI₂-H₂O. Shi S.; Szostak, M. Org. Lett. 2015, 17, 5144 [doi]
4. Sterically-Controlled Pd-Catalyzed Chemoselective Ketone Synthesis via N-C Cleavage in Twisted Amides. Meng, G.; Szostak, M. Org. Lett. 2015, 17 [doi]
5. Recent Developments in the Synthesis and Reactivity of Isoxazoles: Metal Catalysis and Beyond.Hu, F.; Szostak, M. Adv. Synth. Catal. 2015, 357, 2583. [doi]
6. Determination of Structures and Energetics of Small- and Medium-Sized One-Carbon Bridged Twisted Amides using ab Initio Molecular Orbital Methods. Implications for Amidic Resonance along the C-N Rotational Pathway. Szostak, R.; Aubé, J.; Szostak, M. J. Org. Chem. 2015, 80, 7905. [doi]
7. An Efficient Computational Model to Predict Protonation at the Amide Nitrogen and Reactivity along the C-N Rotational Pathway. Szostak, R.; Aubé, J.; Szostak, M. Chem. Commun. 2015, 51, 6395.[doi]
8. Pd-Catalyzed C-H Activation: Expanding the Portfolio of Metal-Catalyzed Functionalization of Unreactive C-H Bonds by Arene-Chromium π-Complexation. Hu, F.; Szostak, M. ChemCatChem2015, 7, 1061. [doi]
9. Highly Chemoselective Reduction of Amides (Primary, Secondary and Tertiary) to Alcohols using SmI₂/H₂O/Amine under Mild Conditions. Szostak, M.; Spain, M.; Eberhart, A. J.; Procter, D. J. J. Am. Chem. Soc. 2014, 136, 2268. [doi]
10. Substrate-Directable Electron Transfer Reactions. Dramatic Rate Enhancement in the Chemoselective Reduction of Cyclic Esters using SmI₂-H₂O: Mechanism, Scope and Synthetic Utility. Szostak, M.; Spain, M.; Choquette, K. A.; Flowers, R. A., II; Procter, D. J. J. Am. Chem. Soc.2013, 135, 15702. [doi]
11. Selective Reduction of Barbituric Acids using SmI₂-H₂O: Synthesis, Reactivity and Structural Analysis of Tetrahedral Adducts. Szostak, M.; Spain, M.; Behlendorf, M; Procter, D. J. Angew. Chem. Int. Ed. 2013, 52, 12559. [doi]
12. Non-Classical Lanthanide(II) Iodides: Uncovering the Importance of Proton Donors in TmI₂-Promoted Electron Transfer. Facile C-N Bond Cleavage in Unactivated Amides. Szostak, M.; Spain, M.; Procter, D. J. Angew. Chem. Int. Ed. 2013, 52, 7237. [doi]
13. Chemistry of Bridged Lactams and Related Heterocycles. Szostak, M.; Aubé, J. Chem. Rev. 2013,113, 5701. [doi]

For more detail, please see the Szostak Group Web Site 

GROUP

Prof. Michal Szostak

Assistant Professor

Ph.D., University of Kansas (2009) with Jeffrey Aubé

Postdoctoral, Princeton University (2010) with David MacMillan

Postdoctoral, University of Manchester (2011-2014) with David Procter 

Postdoctoral Researchers

Dr. Feng Hu

Ph.D., Nanjing University, 2009 (Z. Huang)

Postdoctoral, Shanghai Institute of Materia Medica (Y. Hu)

Research Assistant Professor, SIOC (Q. Shen)

Postdoctoral, Lamar University (X. Lei) 

Dr. Pradeep Nareddy

Ph.D., University of Geneva, 2013 (C. Mazet)

Postdoctoral, Leipzig University (C. Schneider) 

Graduate Students

Shicheng Shi

M.S., SIOC, 2013 (R. Wang)

B.S., Nanjing Agriculture University, 2010 

Guangrong Meng

M.S., Fudan University, 2014 (Q. Zhang)

B.S., Dalian Medical University, 2011 

Chengwei Liu

M.S., Soochow University, 2014 (Y. Yao)

B.S., Zaozhuang University, 2011 

Undergraduate Students

Syed Huq (Rutgers, Chemistry, 2014-present)

Marcel Achtenhagen (Rutgers, Chemistry, 2015-present) 

Visiting Students

Yongmei Liu (Yangzhou University, R. Liu)

//////Nickel-Catalyzed,  Decarbonylative Suzuki–Miyaura Coupling,  Amides, Biaryls

Mia N. Burhardt, Andreas Ahlburg, and Troels Skrydstrup*
dx.doi.org/10.1021/jo5009965
J. Org. Chem., 2014 Articles ASAP read more →


 A catalytic protocol for synthesis of thioesters from aryl, vinyl, and benzyl bromides as well as benzyl chlorides was developed using only stoichiometric amounts of carbon monoxide, produced from a solid CO precursor inside a two-chamber system. As a catalytic system, the combination of bis(benzonitrile) palladium(II) chloride and Xantphos furnished the highest yields of the desired compounds, along with the weak base, NaOAc, in anisole at 120 °C. The choice of catalytic system as well as solvent turned out to be important in order to ensure a high chemoselectivity in the reaction. Both electron-rich and electron-deficient aryl bromides worked well in this reaction. Addition of 1 equiv of sodium iodide to the reaction improved the chemoselectivity with the electron-deficient aryl bromides. The thiol scope included both aryl and alkyl thiols, including 2-mercaptobenzophenones, whereby a thiocarbonylation followed by a subsequent McMurry coupling yielded differently substituted benzothiophenes. It was demonstrated that the methodology could be applied for ¹³C introduction into the thiophene ring.

Palladium-Catalyzed Thiocarbonylation of Aryl, Vinyl, and Benzyl Bromides

Mia N. Burhardt, Andreas Ahlburg, and Troels Skrydstrup^*

Center for Insoluble Protein Structures, Department of Chemistry and Interdisciplinary Nanoscience Center, Aarhus University, Gustav Wieds vej 14, 8000 Aarhus C, Denmark

J. Org. Chem., 2014, 79 (24), pp 11830–11840

DOI: 10.1021/jo5009965

Publication Date (Web): June 12, 2014

Copyright © 2014 American Chemical Society

*E-mail: ts@chem.au.dk.

This article is part of the Mechanisms in Metal-Based Organic Chemistry special issue.

 http://pubs.acs.org/doi/abs/10.1021/jo5009965


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• Supporting Info

Darwinolide

A new rearranged spongian diterpene, darwinolide, has been isolated from the Antarctic Dendroceratid sponge Dendrilla membranosa. Characterized on the basis of spectroscopic and crystallographic analysis, the central seven-membered ring is hypothesized to originate from a ring-expansion of a spongian precursor. Darwinolide displays 4-fold selectivity against the biofilm phase of methicillin-resistant Staphylococcus aureus compared to the planktonic phase and may provide a scaffold for the development of therapeutics for this difficult to treat infection.

 

 NMR Data for Darwinolide (CDCl₃)

position	δC, typea	δH (J in Hz)b	COSY	HMBC	ROESY
1a	38.6, CH2	1.08, m	1b,2a,2b	2,3,4,9,18,19,20
b		1.54, m	1a,2a,2b	2,3,4,5,10,20
2a	18.7, CH2	1.50, m	1b,3a,3b	1,4,10
b		1.59, m	1a,1b,3b	4
3a	39.2, CH2	1.11, m	2a	2,4,18,19
b		1.37, m	2a,2b	4,10,18,19
4	30.8, C
5a	50.5, CH2	1.08, d (14.1)	5b	3,4,9,18,19,20
b		1.38, d (14.1)	5a	1,2,3,4,11,18,19,20
6	15.6, CH3	2.39, d (2.3)	14	7,8,9,13,17	20
7	119.5, C
8	159.5, C
9	57.3, CH	2.08, m	11a,11b	1,5,6,7,8,10,11,12,20	14
10	36.0, C
11a	19.2, CH2	1.42, m	9,12b	8,9,10,12,13,16
b		1.64, m	9,12a,12b	8,9,12,13
12a	25.6, CH2	1.92, m	11b,13	9,13,14,16
b		1.19, m	11a,11b	13,14,16
13	43.2, CH	2.24, m	12a,14,16	12,16
14	45.1, CH	3.93, tt (7.0, 2.4)	6,13,15	7	9,13,15
15	103.9, CH	6.07, d (7.0)	14	7,14,17	14
16	103.8, CH	5.93, s	13	12,13,14,15,21	12a
17	167.7, C
18	33.9, CH3	0.86, s	19	2,3,4,5,10,19	19
19	28.5, CH3	0.98, s	18	3,4,5,10,18	18
20	22.1, CH3	1.14, s		1,5,9,10	6
21	169.7, C
22	21.2, CH3	2.08, s		16,21

a

Recorded at 125 MHz.

b

Recorded at 500 MHz.

 

 

 

 

 

cosy

 

.

roesyad

 

 

Darwinolide, a New Diterpene Scaffold That Inhibits Methicillin-Resistant Staphylococcus aureus Biofilm from the Antarctic Sponge Dendrilla membranosa

Jacqueline L. von Salm^†‡, Christopher G. Witowski^†‡, Renee M. Fleeman^‡§, James B. McClintock^∥, Charles D. Amsler^∥, Lindsey N. Shaw^‡§, and Bill J. Baker^*†‡

^† Department of Chemistry, University of South Florida, 4202 East Fowler Avenue, CHE205, Tampa, Florida 33620, United States

^‡ Center for Drug Discovery and Innovation, University of South Florida, 3720 Spectrum Boulevard, Suite 303, Tampa, Florida 33612, United States

^§ Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, 4202 East Fowler Avenue, ISA2015, Tampa, Florida 33620, United States

^∥ Department of Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States

Org. Lett., 2016, 18 (11), pp 2596–2599

DOI: 10.1021/acs.orglett.6b00979

http://pubs.acs.org/doi/full/10.1021/acs.orglett.6b00979

*E-mail: bjbaker@usf.edu.

 

///////// 

• Supporting Info