Reaction of benzalacetophenone with methylmagnesium iodide. Novel Grignard reaction

1972 ◽  
Vol 37 (17) ◽  
pp. 2747-2748 ◽  
Author(s):  
Richard A. Kretchmer
Keyword(s):  
Grignard Reaction ◽  
Methylmagnesium Iodide

Synthesis of 1,1,5,6-Tetramethyl- and 7-Isopropyl-1,1-dimethyl-1,2,3,4-tetrahydronaphthalene

1999 ◽  
Vol 64 (3) ◽  
pp. 527-532 ◽  
Author(s):  
Ramchandra Bhimrao Mane ◽  
Abhijit Jaysingrao Kadam ◽  
Rajashree Sandeep Salunkhe
Keyword(s):  
Trifluoroacetic Acid ◽  
Polyphosphoric Acid ◽  
Titanium Tetrachloride ◽  
Grignard Reaction ◽  
Butanoic Acid ◽  
Methylmagnesium Iodide

4-(2,3-Dimethylphenyl)butanoic acid (4) was treated with excess of methyllithium to yield 5-(2,3-dimethylphenyl)-2-methylpentan-2-ol (6) which was cyclodehydrated using Dowex 50W-X8 resin, trifluoroacetic acid or polyphosphoric acid (PPA) to furnish 1,1,5,6-tetramethyl-1,2,3,4-tetrahydronaphthalene (1). The acid 4 was cyclized with PPA to furnish 5,6-dimethyl-3,4-dihydronaphthalen-1(2H)-one (5) which was converted into 1 by reaction with dimethylzinc and titanium tetrachloride. 4-(4-Isopropylphenyl)butanoic acid (7) on esterification followed by Grignard reaction with methylmagnesium iodide furnished 5-(4-isopropylphenyl)-2-methylpentan-2-ol (9), which was cyclodehydrated as above to yield 7-isopropyl-1,1-dimethyl-1,2,3,4-tetrahydronaphthalene (2).

Synthesis of the radical scavenger 1,1,3,3-Tetramethylisoindolin-2-yloxyl

1983 ◽  
Vol 36 (2) ◽  
pp. 397 ◽  
Author(s):  
PG Griffiths ◽  
G Moad ◽  
E Rizzardo
Keyword(s):  
Free Radical ◽  
Small Proportion ◽  
Radical Scavenger ◽  
Grignard Reaction ◽  
Radical Trapping ◽  
Methylmagnesium Iodide ◽  
Trapping Agent

A versatile free-radical trapping agent, 1,1,3,3-tetramethylisoindolin-2-yloxyl, has been prepared from N-benzylphthalimide by reaction with 'methylmagnesium iodide' in refluxing toluene followed by hydrogenolysis and oxidation. The Grignard reaction gives 2-benzyl-1,1,3,3-tetramethylisoindoline along with a small proportion of an unexpected by-product, 2-benzyl-1-ethyl-1,3,3-trimethyliso-indoline.

Construction of the Side-Chain in 14β-Androst-5-ene Derivatives. Preparation of 14β-Pregnenolone

1994 ◽  
Vol 59 (12) ◽  
pp. 2691-2704 ◽  
Author(s):  
Ivan Černý ◽  
Miloš Buděšínský ◽  
Pavel Drašar ◽  
Vladimír Pouzar
Keyword(s):  
Nmr Spectra ◽  
Side Chain ◽  
Grignard Reaction ◽  
Diisobutylaluminum Hydride ◽  
Subsequent Oxidation ◽  
Hydride Reduction ◽  
Methylmagnesium Iodide ◽  
A Minor

Stepwise side-chain construction schemes leading to pregnane derivatives were tested in the 14β-androst-5-ene series. 6β-Methoxy-3α,5-cyclo-5α,14β-androstan-17-one (I) gave after methylenation and hydroboration the 17α-hydroxymethyl derivative III. Subsequent oxidation to the aldehyde VI, Grignard reaction with methylmagnesium iodide, and reoxidation led to the ketone VII and to the isomeric 17β-derivative VIII as a minor product. Final i-steroid cleavage of VII furnished the known 14β,17α-pregnenolone IX; the minor product VIII gave the 17β-isomer X. Alternatively, the ketone X was prepared from 6β-methoxy-3α,5-cyclo-5α,14β-androstan-17α-ol p-toluenesulfonate (XI) by cyanide substitution, diisobutylaluminum hydride reduction to the aldehyde XIV, and further as described for IX. The mass and NMR spectra of the four pregnenolone derivatives IX, X, XVIII, and XIX, isomeric in positions 14 and 17, were studied.

Behaviour of 2′-O-p-toluenesulfonyl uridine towards excess of a Grignard reagent

1989 ◽  
Vol 67 (4) ◽  
pp. 708-709 ◽  
Author(s):  
Annie Grouiller ◽  
Hassan Essadiq
Keyword(s):  
Grignard Reagent ◽  
Grignard Reaction ◽  
Methylmagnesium Iodide

Two C-methylated base nucleosides were obtained when 2′-O-tosyl-5′-O-trityluridine was reacted with 30 equivalents of methylmagnesium iodide. Keywords: nucleoside, Grignard reaction, C-methyl pyrimidinone, anhydro derivative, arabinofuranosyl.

Halogenation of ORMOSIL: A Promising Rout for Tailoring Optical Absorptions

2003 ◽  
Vol 771 ◽  
Author(s):  
Amir Fardad ◽  
Wei Liang ◽  
Yadong Zhang ◽  
Bryson Case ◽  
Shibin Jiang ◽  
...  
Keyword(s):  
Process Parameters ◽  
Sol Gel ◽  
Fiber Amplifiers ◽  
Grignard Reaction ◽  
Coupling Loss ◽  
Beam Splitters ◽  
Silicon Technology ◽  
Sol Gel Process ◽  
Propagation Losses ◽  
Signal Intensities

AbstractFluorinated and photo-imageable precursors are synthesized through a Barbier-Grignard reaction for 1550-nm window. The precursors are used for the sol-gel process of integrated optic components for silica-on-silicon technology. Material compositions and process parameters are optimized to achieve internal absorptions >0.1 dB/cm and propagation losses of about 0.5 dB/cm at 1550 nm. Compact 1×16 Beam splitters are designed and fabricated which exhibit >0.3 dB power uniformity, >0.1 dB PDL and 1.5 dB coupling loss. By hybrid integration of the passive splitters and in-house fiber amplifiers, amplifying splitters are demonstrated at various signal intensities.

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.

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