578740-87-1

Upstream product

• 108-05-4 vinyl acetate 
• 578740-82-6 (+/-)-N-carbamoylprolinol 
• 590-28-3 potassium cyanate 
• 498-63-5 2-hydroxymethylpyrrolidine 
• 68832-13-3 D-prolinol 
• 578740-83-7 (+/-)-N-carbamoylprolinol O-acetate 
• 23356-96-9 (S)-1-Pyrrolidin-2-yl-methanol 

Downstream Products

• 20218-56-8 (S)-N-methyl-1-phenylpropan-1-amine 
• 128257-18-1 (R)-N-Methyl-1-phenylpropylamine 
• 128257-11-4 (3S,9aS)-3-Phenyl-hexahydro-pyrrolo[1,2-e][1,3,5]oxadiazepin-5-one 
• 128257-11-4 (3aS,6R)-6-Phenyl-5-oxa-7,8a-diazaperhydroazulen-8-one 

Relevant academic research and scientific papers

Enzyme-catalyzed enantiomeric resolution of N-Boc-proline as the key-step in an expeditious route towards RAMP

For the preparation of both enantiomers of N-carbamoyl-2-methoxymethylpyrrolidine, the precursors of Enders' chiral auxiliaries, SAMP and RAMP, enzyme-catalyzed kinetic resolution of racemic N-carbamoyl, N-Boc, N-Cbz proline esters and prolinols were examined. B. licheniformis protease (subtilisin) preferentially hydrolyzed the (R)-carbamoylproline ester with an enantiomeric ratio (E) of 10. To a hydrophobic N-Cbz proline ester, subtilisin showed lower selectivity (E=2.8), and in contrast, a purified protease (isozyme A) from the earthworm showed the preference of (S)-enantiomer (E=13.6). In a practical sense, C. antarctica lipase B (Chirazyme L-2) was effective for the hydrolysis of both N-Boc and N-Cbz derivatives with E >100. The e.e. of (R)-N-carbamoyl-2-methoxymethylpyrrolidine was raised to be >99.9% by recrystallization at the N-Boc-prolinol stage, which was derived from the (R)-N-Boc-proline methyl ester (98.7% e.e.) through a preparative-scale enzyme-catalyzed resolution (49% yield) of the racemic substrate.

Asymmetric induction by chiral heterocyclic compounds: highly diastereoselective reaction of 5-oxa-7,8a-diazaperhydroazulen-8-ones with organometallic reagents

1) New chiral heterocyclic compounds, 5-oxa-7,8a-diazaperhydroazulen-8-ones (3a-c), were synthesized from (S)-prolinol (1) and potassium cyanate, followed by the condensation with aldehydes. 2) Extremely high diastereoselective reaction of the 3a-c with diethylzinc proceeded with a facil procedure to give (2S,1'S)-N-1'-arylpropyl-2-hydroxymethyl-1-pyrrolidinecarboxamide (4a-c). 3) The reduction of 4a-c with Red-Al gave (S)-1-aryl-N-methylpropylamines (5a-c) and (S)-prolinol (1) in good yields.