ChemInform Abstract: Unexpected endo Selectivity of Conjugate Nucleophilic Addition to an Arene-Cr(CO)3Complex: Enantioselective Synthesis of the Diterpene 11-epi-Helioporin B.

ChemInform ◽  
2010 ◽  
Vol 33 (11) ◽  
pp. no-no
Author(s):  
Florian Dehmel ◽  
Hans-Guenther Schmalz
Keyword(s):  
Nucleophilic Addition ◽  
Enantioselective Synthesis

scholarly journals Catalytic Enantioselective Synthesis of 4-Amino-1,2,3,4-tetrahydropyridine Derivatives from Intramolecular Nucleophilic Addition Reaction of Tertiary Enamides

Synlett ◽  
2018 ◽  
Vol 30 (04) ◽  
pp. 483-487 ◽  
Author(s):  
Shuo Tong ◽  
Mei-Xiang Wang
Keyword(s):  
Phosphoric Acid ◽  
Asymmetric Catalysis ◽  
Nucleophilic Addition ◽  
Addition Reaction ◽  
Enantioselective Synthesis ◽  
Chiral Phosphoric Acid ◽  
Substrate Engineering ◽  
Nucleophilic Addition Reaction ◽  
Engineering Strategy ◽  
Acid Catalyzed

A general and efficient method for the synthesis of highly enantiopure 4-amino-1,2,3,4-tetradydropyridine derivatives based on chiral phosphoric acid catalyzed intramolecular nucleophilic addition of tertiary enamides to imines has been developed. We have also demonstrated a substrate engineering strategy to significantly improve the enantioselectivity of asymmetric catalysis

Novel enantioselective synthesis of (S)-ketamine using chiral auxiliary and precursor Mannich base

2019 ◽  
Vol 97 (5) ◽  
pp. 331-336 ◽  
Author(s):  
Seyed Jamaladdin Gohari ◽  
Abdollah Javidan ◽  
Abolghasem Moghimi ◽  
Mohammad Javad Taghizadeh ◽  
Maryam Iman
Keyword(s):  
Acid Solution ◽  
Nucleophilic Addition ◽  
Grignard Reagent ◽  
Mannich Base ◽  
Enantioselective Synthesis ◽  
Chiral Auxiliary ◽  
Chiral Auxiliaries ◽  
Anesthetic Drug ◽  
Directing Group ◽  
High Yields

Ketamine has been extensively used as an anesthetic drug. Chiral auxiliaries such as tert-butanesulfinamide (TBSA) can be used for the asymmetric synthesis of (S)-ketamine. Condensation of TBSA with ketones provides tert-butanesulfinylimines in consistently high yields. The tert-butanesulfinyl group actuates the imine for nucleophilic addition, is a potent chiral directing group, and after nucleophilic addition is easily dissociated by intervention with acid solution. To prepare 2-(N-piperidinomethyl)-1-phenylcyclohexylamine (1), we started with the cyclohexanone and using Mannich reaction achieved an aminoketone. Then, we made the sulfiniylamin (2) by the condensation of TBSA with aminoketone. By using salts such as Ti(OEt)4, we obtained N-tert-butanesulfinylketimine in 85% yield. Next, we provided a new chiral center (3) using Grignard reagent as nucleophile at −78 °C (80% yield). Finally, after many steps, the (S)-ketamine synthesized under ozonolysis conditions, with good yield and enantioselectivity (75% yield and 75% ee).

Enantioselective Synthesis of α-Methylene-γ-Lactams. Nucleophilic Addition of a Chirally Modified β-Functionalized Allylboronate Reagent to Imines

Synlett ◽  
1998 ◽  
Vol 1998 (3) ◽  
pp. 275-276 ◽  
Author(s):  
Isabelle Chataigner ◽  
Françoise Zammattio ◽  
Jacques Lebreton ◽  
Jean Villiéras
Keyword(s):  
Nucleophilic Addition ◽  
Enantioselective Synthesis
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