t-butyl 5-phenyl-(E,E)-pentadienoate → (3R,alphaS)-t-Butyl 3-(N-allyl-alpha-methylbenzylamino)-5-phenyl-4-pentenoate

HRID 1637035Notes

Reaction equation

[CH2:1]([NH:4][C@@H:5]([CH3:12])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)[CH:2]=[CH2:3].C([Li])CCC.[C:18]1(/[CH:24]=[CH:25]/[CH:26]=[CH:27]/[C:28]([O:30][C:31]([CH3:34])([CH3:33])[CH3:32])=[O:29])[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1>>[CH2:1]([N:4]([C@@H:5]([CH3:12])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)[C@@H:26]([CH:25]=[CH:24][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)[CH2:27][C:28]([O:30][C:31]([CH3:34])([CH3:32])[CH3:33])=[O:29])[CH:2]=[CH2:3]

Participants

Reactant 3

HCID 10857278t-butyl 5-phenyl-(E,E)-pentadienoate

HCID 10899069(S)-N-allyl-alpha-methylbenzylamine

HCID 178418339Butyllithium

Product 1

HCID 86755224(3R,alphaS)-t-Butyl 3-(N-allyl-alpha-methylbenzylamino)-5-phenyl-4-pentenoateYield 98%

Procedure

The procedure of Example 1 was repeated using (S)-N-allyl-α-methylbenzylamine (2) (0.840 g, 5.22 mmol), 1.6M butyllithium (2.16 ml, 4.17 mmol) and t-butyl 5-phenyl-(E,E)-pentadienoate (19) (0.800 g, 3.48 mmol) as the Michael acceptor. Flash chromatography on silica gel [ethyl acetate/petroleum ether (1:19)] afforded the title compound (20) as a colourless oil (1.33 g, 98%). δH (200 MHz; CDCl3) 7.48-7.21 (10H, m, Ph), 6.48 (1H, d, J=16.0, PhCH=CH), 6.25 (1H, dd, J=16.0 and 7.4, PhCH=CH), 5.85 (1H, m, NCH2CH=CH2), 5.15 (1H, app. dd, J=17.3 and 1.6, trans NCH2CH=CH), 5.07 (1H, app. dd, J=10.3 and 1.5, cis NCH2CH=CH2), 4.09 (2H, m, PhCHCH3 and PhCH=CHCH), 3.22 (2H, d, J=6.1, NCH2), 2.56 (1H, dd, J=14.3 and 6.6, CH2CO2), 2.42 (1H, dd, J=14.3 and 8.2, CH2CO2), 1.43 (3H, m, PhCHCH3), 1.42 (9H, s, (CH3)3C).

Sources & evidence

ORD record: ord-c40259b588d84ab9976b152754748ed3
Source dataset: uspto-grants-2000_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06037498

Reaction notes

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