Triisopropyl borate → (1S,2RS)-4-[2-(tert-butyldimethylsilanyloxy)-1-methyl-4-pyridin-3-ylbutoxy]benzeneboronic acid

HRID 379971Notes

Reaction equation

HRID 379971 reaction equation
C([Li])(C)(C)C.Br[C:7]1[CH:32]=[CH:31][C:10]([O:11][C@H:12]([CH:14]([O:23][Si:24]([C:27]([CH3:30])([CH3:29])[CH3:28])([CH3:26])[CH3:25])[CH2:15][CH2:16][C:17]2[CH:18]=[N:19][CH:20]=[CH:21][CH:22]=2)[CH3:13])=[CH:9][CH:8]=1.C([O:36][B:37](OC(C)C)[O:38]C(C)C)(C)C>O1CCCC1>[Si:24]([O:23][CH:14]([CH2:15][CH2:16][C:17]1[CH:18]=[N:19][CH:20]=[CH:21][CH:22]=1)[C@H:12]([CH3:13])[O:11][C:10]1[CH:31]=[CH:32][C:7]([B:37]([OH:38])[OH:36])=[CH:8][CH:9]=1)([C:27]([CH3:30])([CH3:29])[CH3:28])([CH3:26])[CH3:25]

Participants

5

Reactant 3

HCID 21531Triisopropyl borateHCID 20692755(3RS,4S)-3-[4-(4-Bromophenoxy)-3-(tertbutyldimethylsilanyloxy)pentyl]pyridineHCID 178418306HCID 178418306, compound

Product 1

HCID 20692753(1S,2RS)-4-[2-(tert-butyldimethylsilanyloxy)-1-methyl-4-pyridin-3-ylbutoxy]benzeneboronic acid

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
-78 °C

Procedure

A solution of tert-butyllithium (2.5 ml, 1.7M in hexanes) was added over a 1 hour period to a solution of (2S,3RS)-2-(4-bromophenoxy)-3-tert-butyldimethylsilyloxy-5-pyridin-3-ylpentane (1.60 g, Example 5b)) and triisopropylborate (1.07 ml) in tetrahydrofuran (25 ml) at −78° C. The resulting solution was stirred at −78° C. for 2 hours and was then quenched by the addition of a saturated solution of ammonium chloride in water (50 ml). The mixture was poured into water (50 ml) and extracted into ethyl acetate (2×50 ml). The combined extracts were dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by chromatography on silica eluting with ethyl acetate and then ethyl acetate:methanol (4:1) to afford the sub-title compound as a foam (1.2 g).

Workup

  1. customwas then quenched by the addition of a saturated solution of ammonium chloride in water (50 ml)
  2. additionThe mixture was poured into water (50 ml)
  3. extractionextracted into ethyl acetate (2×50 ml)
  4. dry with materialThe combined extracts were dried over anhydrous magnesium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customThe residue was purified by chromatography on silica eluting with ethyl acetate

Sources & evidence

ORD record
ord-88f44b94187440eaabdccdf391b986d5
Source dataset
uspto-grants-2001_10
Patent number
US06300352B1

Reaction notes

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