757994-56-2

Upstream product

• 870-63-3 prenyl bromide 
• 757994-54-0 (S)-2,3,4,5,2',5'-Hexahydro-[1,3']bipyrrolyl-1',5'-dicarboxylic acid 1'-benzyl ester 5'-methyl ester 
• 16217-15-5 1-benzyloxycarbonyl-4-oxo-L-proline methyl ester 

Downstream Products

• 757994-60-8 N-benzyloxycarbonyl-4α-hydroxyl-3α-(3-methylbuten-3-yl)-L-proline methyl ester 
• 757994-68-6 (2S,3R,4R)-4-Hydroxy-3-(3-methyl-but-2-enyl)-pyrrolidine-1,2-dicarboxylic acid 1-benzyl ester 

Relevant academic research and scientific papers

Carboxy mediated stereoselective reduction of ketones with sodium triacetoxyborohydride: Synthesis of novel 3,4-fused tetrahydropyran and tetrahydrofuran prolines

In the presence of a carboxyl group positioned for participation, NaBH(OAc)3 will reduce the usually unreactive ketones in a stereoselective manner. This reaction was applied in a key step to prepare precursors 7 and 15 toward the title compounds 1 and 2. These results are consistent with the exchange of one of the acetoxy groups in the reducing agent with the carboxy group followed by intramolecular delivery of the hydride.