Triphenylphosphine → (2S)-1-bromo-3-(tert-butoxy)-2-methylpropane
Reaction equation
[C:1]([O:5][CH2:6][C@H:7]([CH3:10])[CH2:8]O)([CH3:4])([CH3:3])[CH3:2].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[Br:30]N1C(=O)CCC1=O>C(Cl)Cl>[C:1]([O:5][CH2:6][C@H:7]([CH3:10])[CH2:8][Br:30])([CH3:4])([CH3:3])[CH3:2]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of 25.8 g. (0.176 mole) of (R)-(+)-3-tert. butoxy-2-methyl-1-propanol and 50.5 g. (0.193 mole) of triphenylphosphine in 105 ml. of CH2Cl2 was stirred while 32.8 g. (0.184 mole) of N-bromosuccinimide was added in portions, keeping the temperature below 30° C. with occasional ice bath cooling. The resulting solution was stirred at room temperature for one hour then most of the solvent was distilled under a water aspirator pressure using a Vigreaux column. The product was distilled from the residue using a short distilling head giving 0.7 g. of forerun b.p. 58°-62° C. (23 mm Hg) and then the main fraction (31.1 g.) b.p. 62°-69° C. (14-18 mm Hg). The total distillate (31.8 g.) was chromatographed on 450 g. of silica gel. Elution with 19:1 parts by volume and 9:1 parts by volume hexane-ether yielded the pure (S)-(+)-3-tert. butoxy-2-methyl- 1-bromopropane which was distilled giving 26 g. (70.6%) of colorless liquid, b.p. 71° C. (16 mm Hg); [α]25D+23.32° (c 4.23, C6H6).
Workup
- customthe temperature below 30° C.
- temperaturecooling
- distillationmost of the solvent was distilled under a water aspirator pressure
- distillationThe product was distilled from the residue
- customgiving 0.7 g
- distillationThe total distillate (31.8 g.) was chromatographed on 450 g
- washElution with 19:1 parts by volume and 9:1 parts by volume hexane-ether
Sources & evidence
- ORD record
- ord-9383a434f63c433e95f26df294a72fa4
- Source dataset
- uspto-grants-1980_03
- Patent number
- US04191842
Reaction notes
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