Phosphorus oxychloride → 1,2-Dihydro-6-phenylindolo[1,7-ab][1,5]benzodiazepine

HRID 2052704Notes

Reaction equation

HRID 2052704 reaction equation
F[C:2]1[CH:25]=[CH:24][CH:23]=[CH:22][C:3]=1[C:4]([NH:6][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][C:8]=1[N:13]1[C:21]2[C:16](=[CH:17][CH:18]=[CH:19][CH:20]=2)[CH2:15][CH2:14]1)=O.P(Cl)(Cl)(Cl)=O>C(O)C>[C:3]1([C:4]2[C:20]3[CH:19]=[CH:18][CH:17]=[C:16]4[C:21]=3[N:13]([CH2:14][CH2:15]4)[C:8]3[CH:9]=[CH:10][CH:11]=[CH:12][C:7]=3[N:6]=2)[CH:22]=[CH:23][CH:24]=[CH:25][CH:2]=1

Participants

4

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 203763311-[2-(2-Fluorobenzamido)phenyl]indoline

Product 1

HCID 125191401,2-Dihydro-6-phenylindolo[1,7-ab][1,5]benzodiazepine

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of 15.0 g of 1-(2-benzamidophenyl)indoline of Example 19, and 45 ml of phosphorus oxychloride is refluxed under N2 for 4 hours and then the excess reagent is removed to leave a syrup which is dissolved in absolute ethanol, boiled one hour, then concentrated again to a dark purple syrup which eventually solidifies affter prolonged standing. This material is slurried in absolute ethanol, and treated dropwise with enough Bu3N to change the color from purple to orange-brown, whereupon the product base crystallizes voluminously. After refrigeration overnight, the resultant orange-brown flakes are collected, washed with ethanol and hexane, and dried to afford 1,2-dihydro-6-phenylindolo[1,7-ab][1,5]benzodiazepine, m.p.141°-143° C.

Workup

  1. customthe excess reagent is removed
  2. customto leave a syrup which
  3. concentrationconcentrated again to a dark purple syrup which
  4. additiontreated dropwise with enough Bu3N
  5. customcrystallizes voluminously
  6. waitAfter refrigeration overnight
  7. customthe resultant orange-brown flakes are collected
  8. washwashed with ethanol and hexane
  9. customdried

Sources & evidence

ORD record
ord-376bb8471b214d0f8e443a9d62df27f6
Source dataset
uspto-grants-1980_01
Patent number
US04186199

Reaction notes

Loading…