Efficient synthesis of vinyl ethers of spiroquinol ketals and their high-yield photochemical oxygen-to-carbon [1,3]-shift to spiro-fused 2,5-cyclohexadienones

1992 ◽  
Vol 57 (1) ◽  
pp. 78-85 ◽  
Author(s):  
John S. Swenton ◽  
Andrew Callinan ◽  
Shaopeng Wang
Keyword(s):  
High Yield ◽  
Efficient Synthesis ◽  
Vinyl Ethers

scholarly journals Multistep batch-flow hybrid synthesis of a terbinafine precursor

2021 ◽  
Author(s):  
Tamás Hergert ◽  
Béla Mátravölgyi ◽  
Róbert Örkényi ◽  
János Éles ◽  
Ferenc Faigl
Keyword(s):  
Methyl Ether ◽  
Lithium Salt ◽  
Scale Up ◽  
Hybrid Process ◽  
High Yield ◽  
Grignard Reaction ◽  
Efficient Synthesis ◽  
Synthetic Process ◽  
Synthesis Route ◽  
Selective Addition

AbstractA three-step batch-flow hybrid process has been developed for an expeditious synthesis of the enynol key intermediate of antifungal terbinafine. This procedure involves consecutive organometallic steps without the necessity of any in-line purification: after a metalation by n-butyllithium, a selective addition of the lithium salt was elaborated followed by a Grignard reaction resulting in a high yield of 6,6-dimethylhept-1-en-4-yn-3-ol. Moreover, as an alternative to tetrahydrofuran, cyclopentyl methyl ether was used as solvent implementing a safe, sustainable, yet selective synthetic process. Even on a laboratory-scale, the optimized batch-flow hybrid process had a theoretical throughput of 41 g/h. Furthermore, the newly developed process provides an efficient synthesis route to the key-intermediate, while making acrolein obsolete, minimizing side-products, and enabling safe and convenient scale-up.

Enantioselective synthesis of (R)-tolterodine using lithiation/borylation–protodeboronation methodology

2012 ◽  
Vol 90 (11) ◽  
pp. 965-974 ◽  
Author(s):  
Stefan Roesner ◽  
Varinder K. Aggarwal
Keyword(s):  
Enantioselective Synthesis ◽  
High Yield ◽  
Magnesium Bromide ◽  
Efficient Synthesis ◽  
Boronic Ester ◽  
Better Than

The synthesis of the pharmaceutical (R)-tolterodine is reported using lithiation/borylation–protodeboronation of a homoallyl carbamate as the key step. This step was tested with two permutations: an electron-neutral aryl Li-carbamate reacting with an electron-rich boronic ester and an electron-rich aryl Li-carbamate reacting with an electron-neutral boronic ester. It was found that the latter arrangement was considerably better than the former. Further improvements were achieved using magnesium bromide in methanol leading to a process that gave high yield and high enantioselectivity in the lithiation/borylation reaction. The key step was used in an efficient synthesis of (R)-tolterodine in a total of eight steps in a 30% overall yield and 90% ee.

scholarly journals Glycosylation of Stannyl Ceramides Promoted by Modified Montmorillonite­ in Supercritical Carbon Dioxide

Synthesis ◽  
2017 ◽  
Vol 50 (03) ◽  
pp. 593-598
Author(s):  
José Morales-Serna ◽  
Bao Nguyen ◽  
Eréndira García-Ríos ◽  
Rubén Gaviño ◽  
Jorge Cárdenas ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
High Yield ◽  
Efficient Synthesis ◽  
Supercritical Carbon

The direct glycosylation of ceramides in supercritical carbon dioxide (scCO2) successfully proceeded to produce β-glycolipids in high yield and with full stereoselectivity. The reaction is promoted by montmorillonite modified with a superacid (CF3SO3H). The value of this protocol was demonstrated in the efficient synthesis of isoglobotrihexosylceramide (iGB3).

Efficient Synthesis of Substituted Vinyl Ethers Using the Julia Olefination

2003 ◽  
Vol 5 (25) ◽  
pp. 4851-4854 ◽  
Author(s):  
Simon Surprenant ◽  
Wing Yan Chan ◽  
Carl Berthelette
Keyword(s):  
Efficient Synthesis ◽  
Vinyl Ethers ◽  
Julia Olefination

Efficient synthesis of alkyl aryl ketones & ketals via palladium-catalyzed regioselective arylation of vinyl ethers

2010 ◽  
Vol 8 (9) ◽  
pp. 2012 ◽  
Author(s):  
Mingcui Liu ◽  
Zeynab Hyder ◽  
Yawei Sun ◽  
Weijun Tang ◽  
Lijin Xu ◽  
...  
Keyword(s):  
Efficient Synthesis ◽  
Vinyl Ethers ◽  
Alkyl Aryl ◽  
Aryl Ketones ◽  
Palladium Catalyzed

Bromination of Tetralin. Short and Efficient Synthesis of 1,4-Dibromonaphthalene

2000 ◽  
Vol 65 (11) ◽  
pp. 1791-1804 ◽  
Author(s):  
Osman Çakmak ◽  
Ismail Kahveci ◽  
Íbrahim Demirtaş ◽  
Tuncer Hökelek ◽  
Keith Smith
Keyword(s):  
High Temperature ◽  
Major Product ◽  
High Yield ◽  
Efficient Synthesis ◽  
Secondary Products ◽  
Derivatives Of ◽  
Sole Product

High-temperature bromination of tetralin (1,2,3,4-tetrahydronaphthalene) with bromine resulted in benzylic bromination to give 1,4-dibromo-1,2,3,4-tetrahydronaphthalene (4) as a major product and several secondary products. Photolytic bromination of tetralin and subsequent double dehydrobromination of 1,1,4,4-tetrabromo-1,2,3,4-tetrahydronaphthalene (10) gave 1,4-dibromonaphthalene (11) as the sole product in a high yield. 1,4-Dibromonaphthalene is efficiently converted to the corresponding methoxy (12 and 13) and cyano (14 and 15) derivatives of naphthalene.

scholarly journals An Efficient Synthesis of 1,8-Dioxo-Octahydroxanthenes Derivatives Using Heterogeneous Ce-ZSM-11 Zeolite Catalyst

2018 ◽  
Vol 13 (3) ◽  
pp. 436 ◽  
Author(s):  
Rameshwar R. Magar ◽  
Ganesh T. Pawar ◽  
Sachin P. Gadekar ◽  
Machhindra Karbhari Lande
Keyword(s):  
Zeolite Catalyst ◽  
Bet Surface Area ◽  
High Yield ◽  
Efficient Synthesis ◽  
X Ray Diffraction ◽  
One Pot ◽  
Efficient Catalyst ◽  
Temperature Programmed ◽  
The One ◽  
Work Up

The Ce-ZSM-11 zeolite has been used as an efficient catalyst for the one pot synthesis of 1,8-dioxo-octahydroxanthene derivatives from aromatic aldehyde and 5,5-dimethyl-cyclohexane-1,3-dione under reflux condition. The catalyst was characterized by Powder X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmer-Teller (BET) surface area analysis, and Temperature Programmed Desorption (TPD) techniques. This method provides several advantageous such as use of inexpensive catalyst, simple work-up procedure, high yield of desired product and reusability of catalyst. Copyright © 2018 BCREC Group. All rights reservedReceived: 5th January 2018; Revised: 25th May 2018; Accepted: 27th May 2018How to Cite: Magar, R.R., Pawar, G.T., Gadekar, S.P., Lande, M.K. (2018). An Efficient Synthesis of  1,8-Dioxo-Octahydroxanthenes Derivatives Using Heterogeneous Ce-ZSM-11 Zeolite Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 436-446 (doi:10.9767/bcrec.13.3.2062.436-446)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2062.436-446 

An Efficient Synthesis of 5,5′-(Tetradecane-1,14-diyl)bis(2-methylbenzene-1,3-diol) and Related Substances

1997 ◽  
Vol 50 (7) ◽  
pp. 747 ◽  
Author(s):  
Van H. Tran ◽  
Basil D. Roufogalis ◽  
Colin C. Duke
Keyword(s):  
Minor Component ◽  
High Yield ◽  
Efficient Synthesis ◽  
Related Substances ◽  
Other Substances ◽  
A Minor

An efficient and versatile method was developed to synthesize 5,5′-(tetradecane-1,14-diyl)bis(2-methylbenzene-1,3-diol) (striatol), a minor component of the plant Grevillea striata (Proteaceae family). Other substances prepared in high yield by the method include 5,5′-(dodecane-1,12-diyl)bis(2-methylbenzene-1,3-diol), 5,5′-(decane-1,10-diyl)bis(2-methylbenzene-1,3-diol), 5,5′-(octane-1,8-diyl)bis(2-methylbenzene-1,3-diol) and 2-methyl-5-nonylresorcinol

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