Dehydroabietylamine → 99306-87-3

HRID 372183Notes

Reaction equation

HRID 372183 reaction equation
[CH3:1][CH:2]([C:4]1[CH:9]=[CH:8][C:7]2[C@:10]3([CH3:21])[C@@H:15]([CH2:16][CH2:17][C:6]=2[CH:5]=1)[C@@:14]([CH2:19][NH2:20])([CH3:18])[CH2:13][CH2:12][CH2:11]3)[CH3:3]>CCOCC>[CH3:3][CH:2]([C:4]1[CH:9]=[CH:8][C:7]2[C@:10]3([CH3:21])[C@@H:15]([CH2:16][CH2:17][C:6]=2[CH:5]=1)[C@:14]([CH2:19][NH2:20])([CH3:18])[CH2:13][CH2:12][CH2:11]3)[CH3:1]

Participants

3

Reactant 1

HCID 62034Dehydroabietylamine

Product 1

HCID 1563221299306-87-3

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent2×

Procedure

dl-5-Benzyloxymethyl-cyclopent-2-enyl-4-hydroxy-1-acetic acid (88.5 g.) in ether (1500 ml.) was slowly treated with dehydroabietylamine (92.4 g.) in ether (500 ml.). The precipitated salt (140 g., [α]DMeOH = + 19°) was collected by filtration and was crystallised from benzene (20 ml./g.) to afford a salt (54 g.), [α]D = + 13° (methanol). Two subsequent crystallisations from benzene (50 ml./g; 2 hours at room temperature) gave the dehydroabiethylamine salt of 1-5α-benzyloxymethyl-4β-hydroxycyclopent-2-enyl-1β-acetic acid (42 g.), [α]DMeoH = + 10°. A suspension of this salt in ether-water (2:1) was treated with 1.2 equivalents of 5% potassium hydroxide and extracted with ether. The aqueous layer was then treated with 8N sulphuric acid to pH 1.5, saturated with ammonium sulphate and extracted with chloroform to yield the pure 1- 5α-benzyloxymethyl-4β-hydroxy-cyclopent-2-enyl-1β-acetic acid, which showed [α]D = -26.5°; [α]365° = - 78° (CHCl3) and [α]D = -5.4°. [α]365° = -13° (MeOH). The mother liquors from the first benzene crystallization were diluted with ether to obtain a benzene-ether ratio of 5:4 and stored for 3 hours at 5°. The precipitated salt (48 g., [α]DMeOH = + 27°) was collected by filtration and recrystallised from benzene-ether (1 g. salt, benzene 20 ml., ether 40 ml.) to yield 44 g. of the dehydroabietylamine salt of d-5β-benzyloxymethyl-4α-hydroxycyclopent-2-enyl-1α-acetic acid, [α]DMeOH = + 28.8°. In a similar way, the 5α-p-methoxybenzyloxymethyl-4β-hydroxy-cyclopent-2-enyl-1β-acetic acid was obtained from the dl-acid.

Workup

  1. filtrationThe precipitated salt (140 g., [α]DMeOH = + 19°) was collected by filtration
  2. customwas crystallised from benzene (20 ml./g.)
  3. customto afford a salt (54 g.), [α]D = + 13° (methanol)
  4. customTwo subsequent crystallisations from benzene (50 ml./g; 2 hours at room temperature)

Sources & evidence

ORD record
ord-3bff4d16e37b42329dfa0f191ef7e7e8
Source dataset
uspto-grants-1978_05
Patent number
US04089896

Reaction notes

Loading…