The addition of organometallic reagents to tetramesityldigermene

2002 ◽  
Vol 80 (11) ◽  
pp. 1387-1392 ◽  
Author(s):  
Kyle L Fujdala ◽  
David W.K Gracey ◽  
Erica F Wong ◽  
Kim M Baines
Keyword(s):  
Ligand Exchange ◽  
Grignard Reagent ◽  
Thermal Conditions ◽  
Grignard Reagents ◽  
Ethylmagnesium Bromide ◽  
Organometallic Reagent ◽  
Organometallic Reagents ◽  
Thermal Cleavage

The thermolysis and photolysis of hexamesitylcyclotrigermane in the presence of ethylmagnesium bromide has been investigated. Under photochemical conditions, ethyldimesitylgermane, 1,2-diethyl-1,1,2-trimesityldigermane and ethyl-1,1,2,2-tetramesityldigermane were isolated and, under thermal conditions, 1,2,2-triethyl-1,1-dimesityl digermane and 2,2-diethyl-1,1,1-trimesityldigermane were isolated. The photolysis of hexamesitylcyclotrigermane in the presence of methyllithium has also been investigated. In both cases, the organometallic reagent adds to tetramesityl digermene and dimesitylgermylene formed by photochemical or thermal cleavage of the cyclotrigermane. In the case of the addition of the Grignard reagent, the resulting germyl Grignard reagent undergoes a facile ligand exchange reaction.Key words: digermene, germylene, Grignard reagents, alkyllithium reagents, germylmagnesium compounds, germyllithium compounds.

Grignard reagent formation via C-F bond activation: a centenary perspective

2022 ◽  
Author(s):  
Eunsung Lee ◽  
Ewa Pietrasiak
Keyword(s):  
Bond Dissociation Energy ◽  
Dissociation Energy ◽  
Grignard Reagent ◽  
Bond Activation ◽  
Grignard Reagents ◽  
Bond Dissociation ◽  
High Bond

Examples of Grignard reagents obtained by C-F bond activation with magnesium kept appearing in the literature over the last century. Due to the high bond dissociation energy of the C-F...

Diastereoselective Synthesis of Morpholine Derivatives from Grignard Reagents and N-Sulfinyl Imines

Synlett ◽  
2021 ◽  
Author(s):  
Eric P. A. Talbot ◽  
Joseph M. Bateman ◽  
Diana Chan ◽  
Mustafa Moroglu ◽  
Benjamin Rahemtulla
Keyword(s):  
Grignard Reagent ◽  
Stereoselective Synthesis ◽  
Grignard Reagents ◽  
Diastereoselective Synthesis ◽  
Step Process ◽  
Diastereoselective Addition ◽  
Morpholine Derivatives

The stereoselective synthesis of C3-substituted morpholine derivatives has been achieved through a two-step process involving diastereoselective addition of a Grignard reagent to a sulfinyl imine, followed by cyclization.

Recent Advances in the Synthesis of Enantiomerically Enriched Diaryl, Aryl Heteroaryl, and Diheteroaryl Alcohols through Addition of Organometallic Reagents to Carbonyl Compounds

Synthesis ◽  
2020 ◽  
Vol 52 (13) ◽  
pp. 1855-1873
Author(s):  
Senthil Narayanaperumal ◽  
Ricardo S. Schwab ◽  
Wystan K. O. Teixeira ◽  
Danilo Yano de Albuquerque
Keyword(s):  
Carbonyl Compounds ◽  
Building Blocks ◽  
Short Review ◽  
Biological Properties ◽  
Enantioselective Synthesis ◽  
Grignard Reagents ◽  
Organometallic Reagents ◽  
Important Family ◽  
Organolithium Reagents ◽  
Organozinc Reagents

Enantiomerically enriched diaryl, aryl heteroaryl, and dihetero­aryl alcohols are an important family of compounds known for their biological properties. Moreover, these molecules are highly privileged scaffolds used as building blocks for the synthesis of pharmaceutically relevant products. This short review provides background on the enantioselective arylation and heteroarylation of carbonyl compounds, as well as, the most significant improvements in this field with special emphasis on the application of organometallic reagents.1 Introduction2 Background on the Enantioselective Synthesis of Diaryl, Aryl Heteroaryl, and Diheteroaryl Alcohols3 Organozinc Reagents4 Organolithium Reagents5 Grignard Reagents6 Organoaluminum Reagents7 Organotitanium Reagents8 Organobismuth Reagents9 Miscellaneous10 Conclusion

Use of Menthyl 2-Methoxynaphthalene-1-sulfinates in the Andersen Synthesis of Optically Active Sulfoxides. Facile Cleavage by Grignard Reagents of Some Aromatic Methyl Ethers

1994 ◽  
Vol 47 (10) ◽  
pp. 1925 ◽  
Author(s):  
KH Bell ◽  
LF Mccaffery
Keyword(s):  
Grignard Reagent ◽  
Methoxy Group ◽  
Optically Active ◽  
Grignard Reagents ◽  
Sulfinyl Group

The pure crystalline diastereomers (1R,2S,5R)-menthyl (R)- and (S)-2-methoxynaphthalene-1-sulfinate (1b) have been prepared and, by reaction with Grignard reagents (the Andersen procedure), converted into optically active alkyl and aryl 2-methoxynaphthyl sulfoxides in 67-77% yields. Use of an excess of Grignard reagent results in facile O-alkyl cleavage of the methoxy group to the corresponding naphthol or a competing loss of the alkyl- or aryl- sulfinyl group to form 2-methoxynaphthalene. Pure diastereomers of menthyl 2,7- dimethoxynaphthalene-1-sulfinate (2b) and menthyl 4-methoxynaphthalene-1-sulfinate (3b) have also been prepared and their reactions with Grignard reagents have been studied.

scholarly journals Kinetics and mechanism of the C-S coupling reactions of aryl Grignard reagents with aryl arenesulfonates

2008 ◽  
Vol 6 (2) ◽  
pp. 237-244 ◽  
Author(s):  
Ender Erdik ◽  
Fatma Eroğlu
Keyword(s):  
Nucleophilic Addition ◽  
Kinetic Data ◽  
Grignard Reagent ◽  
Activation Parameters ◽  
Grignard Reagents ◽  
Coupling Reactions ◽  
Sulfonyl Group ◽  
First Order ◽  
Kinetics Of ◽  
Hammett Relationship

AbstractThe kinetics of the C-S coupling of arylmagnesium bromides with phenyl tosylate has been studied in THF: toluene at 90°C. The reaction is first order in Grignard reagent and first order in phenyl tosylate. Kinetic data, Hammett relationship and activation parameters are consistent with a nucleophilic addition mechanism involving rate determining attack of carbanion to sulfonyl group followed by a fast phenoxide group leaving.

Titanacyclopropanes as versatile intermediates for carbon-carbon bond formation in reactions with unsaturated compounds

2000 ◽  
Vol 72 (9) ◽  
pp. 1715-1719 ◽  
Author(s):  
O. G. Kulinkovich
Keyword(s):  
Reaction Mechanism ◽  
Bond Formation ◽  
Grignard Reagents ◽  
Allylic Alcohols ◽  
Ethylmagnesium Bromide ◽  
Carbon Bond ◽  
Unsaturated Compounds ◽  
Carbon Carbon Bond ◽  
Reaction Proceeds

Dialkoxytitanacyclopropane intermediates [or titanium (II)-olefin complexes] generated in situ from ethylmagnesium bromide and titanium (IV) isopropoxide react with allylic alcohols and allylic ethers to afford SN2' allylic ethylation products. The reaction proceeds with high regioselectivity and with low to high trans-/cis-stereoselectivity. This observation and others suggest a reaction mechanism involving an EtMgBr-initiated formation of titanacyclopentane ate complex 10 from titanacyclopropane-olefin complex 7 as a key step. Based on this assumption, a modified mechanism of titanium-mediated cyclopropanation of esters with Grignard reagents is proposed.

Copper-Catalyzed Enantioselective Conjugate Addition to α,β-Unsaturated Aldehydes with Various Organometallic Reagents

Synthesis ◽  
2016 ◽  
Vol 48 (19) ◽  
pp. 3301-3308 ◽  
Author(s):  
Sylvie Goncalves-Contal ◽  
Ludovic Gremaud ◽  
Laëtitia Palais ◽  
Lucille Babel ◽  
Alexandre Alexakis
Keyword(s):  
Bond Formation ◽  
Conjugate Addition ◽  
Chiral Ligands ◽  
Grignard Reagents ◽  
Important Class ◽  
Reaction Conditions ◽  
Organometallic Reagents ◽  
Unsaturated Aldehydes

β-Substituted aldehydes constitute a very important class of compounds found in nature. Synthesis of this motif can be envisioned by C–C bond formation on enals. For this purpose, we report herein the development of enantioselective copper-catalyzed conjugate addition of various organometallic reagents to α,β-unsaturated aldehydes with (R)-H8BINAP, (R)-TolBINAP, and (R)-SEGPHOS as chiral ligands. Three sets of conditions were successfully developed and several enals were used. Reactivity and regio- and enantioselectivities were strongly dependent on reaction conditions and substrates. Good to excellent regio- and enantioselectivities were obtained with zinc reagents R2Zn and aluminum reagents R3Al. However, the asymmetric conjugate addition of Grignard reagents afforded only moderate to good regio- and enantioselectivities.

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