Triethyl borate → [(7R)-7-(dibenzylamino)-5,6,7,8-tetrahydronaphthalen-1-yl]boronic acid

HRID 1099396Notes

Reaction equation

HRID 1099396 reaction equation
[CH2:1]([N:8]([CH2:20][C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1)[C@@H:9]1[CH2:18][CH2:17][C:16]2[C:11](=[C:12](Br)[CH:13]=[CH:14][CH:15]=2)[CH2:10]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C([Li])CCC.[B:32](OCC)([O:36]CC)[O:33]CC>O1CCCC1>[CH2:1]([N:8]([CH2:20][C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1)[C@H:9]1[CH2:10][C:11]2[C:12]([B:32]([OH:36])[OH:33])=[CH:13][CH:14]=[CH:15][C:16]=2[CH2:17][CH2:18]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 3

HCID 9009Triethyl borateHCID 22082960(2R)-N,N-dibenzyl-8-bromo-1,2,3,4-tetrahydronaphthalen-2-amineHCID 178418339Butyllithium

Product 1

HCID 59354908[(7R)-7-(dibenzylamino)-5,6,7,8-tetrahydronaphthalen-1-yl]boronic acidYield 67%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
0 °C

Procedure

To a solution of (2R)-N,N-dibenzyl-8-bromo-1,2,3,4-tetrahydronaphthalen-2-amine (1000 mg, 2.46 mmol) in dry tetrahydrofuran (10 mL) under an atmosphere of nitrogen, n-butyllithium (1.6M, 2.3 mL, 3.69 mmol) was added over 5 min at −70° C. The reaction mixture was stirred at 0° C. for 10 min before triethyl borate (0.50 mL, 2.95 mmol) was added. The reaction mixture was stirred for additional 5 min at 0° C. and then allowed to reach ambient temperature and stirred for another 2 h. The reaction mixture was quenched with saturated ammonium chloride (aq) and a white precipitate was filtered off. The filtrate was extracted with ethyl acetate, the organic layer was dried over magnesium sulfate and concentrated in vacuo to yield 612 mg (67%) of the title compound as a solid: 1H NMR (400 MHz, CDCl3) δ ppm 8.31 (d, 1 H), 7.39-7.45 (m, 4 H), 7.28-7.37 (m, 2 H), 7.02-7.26 (m, 6 H), 3.65-3.92 (m, 4 H), 3.34-3.45 (m, 1 H), 2.70-3.19 (m, 4 H), 2.16 (br. s., 1 H), 1.66-1.79 (m, 1 H); MS (ESI) m/z 371, 372[M+H+].

Workup

  1. additionwas added
  2. customto reach ambient temperature
  3. stirringstirred for another 2 h
  4. customThe reaction mixture was quenched with saturated ammonium chloride (aq)
  5. filtrationa white precipitate was filtered off
  6. extractionThe filtrate was extracted with ethyl acetate
  7. dry with materialthe organic layer was dried over magnesium sulfate
  8. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-66577f75d238499da21a905f60697603
Source dataset
uspto-grants-2012_03
Patent number
US08143408B2

Reaction notes

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