Conjugate addition of Grignard reagents to p-nitrotoluene. Competitive attack of entering alkyl group to ortho and para positions

1978 ◽  
Vol 43 (14) ◽  
pp. 2932-2933 ◽  
Author(s):  
Giuseppe Bartoli ◽  
Marcella Bosco ◽  
Germana Pezzi
Keyword(s):  
Alkyl Group ◽  
Conjugate Addition ◽  
Grignard Reagents

The stereochemistry of conjugate addition of lithium dialkyl cuprate reagents to some carbohydrate α-enones

1977 ◽  
Vol 55 (23) ◽  
pp. 4002-4009 ◽  
Author(s):  
Mark Bernard Yunker ◽  
Dieter Ernest Plaumann ◽  
Bert Fraser-Reid
Keyword(s):  
Alkyl Group ◽  
Heterogeneous Medium ◽  
Complex Mixture ◽  
Conjugate Addition ◽  
Homogeneous System ◽  
Axial Orientation ◽  
Grignard Reagents ◽  
Alkylation Reactions

Conjugate addition-alkylation reactions of lithium dialkyl cuprates to hex-2-enopyrano-4-ulosides (1), hex-3-enopyrano-2-ulosides (2), and hex-1-enopyrano-3-uloses (3) have been investigated. Extensive studies with 1 show that the homogeneous system using the soluble tri-n-butylphosphine copper(I) complex is less satisfactory than the heterogeneous medium in which copper(I) iodide is used. The use of Grignard reagents versus alkyl lithiums has also been investigated, the latter being found preferable. 1,2-Addition was observed in some cases, but conditions were developed to avoid formation of these side products.With α-enones 1 and 2 alkylation is completely stereoselective, the newly introduced alkyl group being in axial orientation. With 3 a complex mixture is obtained from which equatorial and axial adducts can be isolated in approximately equal amounts.

Conjugate Addition of Grignard Reagents to Nitroarenes: A New Synthesis of 9-Alkylanthracenes, 9-Nitro-10-alkylanthracenes, and 10,10-Dialkylanthrones

Synthesis ◽  
1982 ◽  
Vol 1982 (10) ◽  
pp. 836-839 ◽  
Author(s):  
Nicola Armillotta ◽  
Giuseppe Bartoli ◽  
Marcella Bosco ◽  
Renato Dalpozzo
Keyword(s):  
Conjugate Addition ◽  
Grignard Reagents ◽  
New Synthesis
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