Benzyl isocyanate → N-(6-Cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-4-yl)-N'-(phenylmethyl)urea

HRID 1197692Notes

Reaction equation

HRID 1197692 reaction equation
[C:1]([C:3]1[CH:4]=[CH:5][C:6]2[O:11][C:10]([CH3:13])([CH3:12])[C@@H:9](O)[C@H:8]([N:15](C3C=CN=CC=3)[C:16]([NH2:18])=[O:17])[C:7]=2[CH:25]=1)#[N:2].[CH2:26](N=C=O)[C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1>C(O)C>[C:1]([C:3]1[CH:4]=[CH:5][C:6]2[O:11][C:10]([CH3:12])([CH3:13])[CH2:9][CH:8]([NH:15][C:16]([NH:18][CH2:26][C:27]3[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=3)=[O:17])[C:7]=2[CH:25]=1)#[N:2]

Participants

4

Reactant 2

HCID 76639Benzyl isocyanateHCID 67809575(trans)-1-(6-Cyano-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-yl)-(4-pyridinyl)urea

Product 1

HCID 15295557N-(6-Cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-4-yl)-N'-(phenylmethyl)ureaYield 89.7%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of (-)-4-amino-6-cyano-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran (2.0 g, 9.9 mmole, from Example 19, part B) and benzyl isocyanate (1.32 g, 9.9 mmole) in ethanol (15 ml) under argon was heated at reflux for two hours. The solvent ws recovered under vacuum and the crude product was triturated with isopropyl ether to obtain 2.98 g (89.7%) of the title compound as a pure white solid. m.p.=140-141° C., [α]D25DMF=-41.2°. 1H NMR (DMSO-d6) δ 7.59 (s, 1H), 7.56 (d. J=1.76 Hz, 1H), 7.38-7.22 (m, 5H), 6.89 (d, J=8.21 Hz, 1H), 6.56 (t, J=5.87 Hz, 1H), 6.49 (d, J=8.79 Hz, 1H), 4.94 (m, 1H), 4.30 (d, J=5.87 Hz, 1H), 2.11(dd, J=6.16 and 13.19 Hz, 1H), 1.74 (d, J=12.32 Hz, 1H), 1.41 (s. 3H), 1.28 (s, 3H). 13C NMR (DMSO-d) δ 158.19, 157.27, 140.80, 132.25, 132.15, 128.31, 126.98, 126.69, 126.18, 119.28, 118.13, 102.06., 77.37, 43.08, 42.01, 37.80, 29.15, 24.47. MS: (M+H)+ @336.

Workup

  1. temperatureat reflux for two hours
  2. customThe solvent ws recovered under vacuum
  3. customthe crude product was triturated with isopropyl ether

Sources & evidence

ORD record
ord-ca4df4b461304ff996eb7905ae77885d
Source dataset
uspto-grants-1994_01
Patent number
US05276168

Reaction notes

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