Diisobutylaluminumhydride → (2S,4R)-5-benzyloxy-2-(tert-butoxycarbonyl)amino-4-methylpentanoic acid methyl ester

HRID 1684750Notes

Reaction equation

HRID 1684750 reaction equation
[C:1]([O:5][C:6]([NH:8][C@@H:9]([CH2:22][C@H:23]([CH2:27][O:28][CH2:29][C:30]1[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=1)[CH:24](C)C)[C@@H:10]([OH:21])CC(=C)C(NCCCC)=O)=[O:7])([CH3:4])([CH3:3])[CH3:2].[C:36]([O:40][C:41]([NH:43][C@@H:44]([CH2:57][C@H:58]([CH2:62][O:63][CH2:64][C:65]1[CH:70]=[CH:69][CH:68]=[CH:67][CH:66]=1)[CH:59](C)C)[C@H:45]([OH:56])CC(=C)C(NCCCC)=O)=[O:42])([CH3:39])([CH3:38])[CH3:37].[H-].C([Al+]CC(C)C)C(C)C>C1(C)C=CC=CC=1>[CH3:36][O:40][C:10](=[O:21])[C@@H:9]([NH:8][C:6]([O:5][C:1]([CH3:2])([CH3:3])[CH3:4])=[O:7])[CH2:22][C@@H:23]([CH3:24])[CH2:27][O:28][CH2:29][C:30]1[CH:31]=[CH:32][CH:33]=[CH:34][CH:35]=1.[CH2:64]([O:63][CH2:62][C@H:58]([CH3:59])[CH2:57][C@H:44]([NH:43][C:41]([O:40][C:36]([CH3:39])([CH3:38])[CH3:37])=[O:42])[CH:45]=[O:56])[C:65]1[CH:66]=[CH:67][CH:68]=[CH:69][CH:70]=1

Participants

6

Reactant 3

HCID 21225700DiisobutylaluminumhydrideHCID 57011577HCID 57011577, compoundHCID 57309556HCID 57309556, compound

Product 2

HCID 69646373(2S,4R)-5-benzyloxy-2-(tert-butoxycarbonyl)amino-4-methylpentanoic acid methyl esterHCID 86604678(2S,4R)-5-benzyloxy-2-(tert-butoxycarbonyl)amino-4-methyl-pentanal

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

(2S,3S,5R)-2-[6-Benzyloxy-3-(tert-butoxycarbonyl)amino-2-hydroxy-5-methylhexyl]-N-(butyl)acrylamide (A) and (2R,3S,5R)-2-[6-benzyloxy-3-(tert-butoxycarbonyl)amino-2-hydroxy-5-methylhexyl]-N-(butyl)acrylamide (B): In a manner analogous to that described in Example 1h), there is obtained first, by reduction of (2S,4R)-5-benzyloxy-2-(tert-butoxycarbonyl)amino-4-methylpentanoic acid methyl ester (9.51 g) in the presence of a 1.2M diisobutylaluminium hydride solution in toluene, (2S,4R)-5-benzyloxy-2-(tert-butoxycarbonyl)amino-4-methyl-pentanal (8.2 g of crude product) in the form of a pale-yellow oil. The crude aldehyde is reacted in a manner analogous to that described in Example 1g) without being purified further. The crude product (17.1 g) so obtained comprises an approximately 1:1.45 mixture of the two diastereoisomers A and B. Purification by column chromatography with separation of the two stereoisomers on silica gel (0.6 kg, eluant gradient from C to E) yields title compound A (2.05 g) in the form of a waxy solid, Rf (E)=0.43, MS(FAB) m/e 463 (M+ +1), and title compound B (3.01 g) in the form of a light-yellow oil, Rf (E)=0.35, MS(FAB) m/e 463 (M+ +1).

Sources & evidence

ORD record
ord-0d2de69977064977948416ad63ef5f2f
Source dataset
uspto-grants-1997_06
Patent number
US05641778

Reaction notes

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