Iodine → HCID 54081156, compound

HRID 2118933Notes

Reaction equation

HRID 2118933 reaction equation
[Mg].II.C(Br)C.[C:7]1([C:13]#[CH:14])[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1.[O:15]([C:22]1[CH:23]=[C:24]([CH:27]=[CH:28][CH:29]=1)[CH:25]=[O:26])[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1>O1CCCC1.Cl>[O:15]([C:22]1[CH:23]=[C:24]([CH:27]=[CH:28][CH:29]=1)[CH:25]([OH:26])[C:14]#[C:13][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)[C:16]1[CH:17]=[CH:18][CH:19]=[CH:20][CH:21]=1

Participants

8

Reactant 5

HCID 807IodineHCID 6332Ethyl BromideHCID 10821PhenylacetyleneHCID 382843-PhenoxybenzaldehydeHCID 5462224Magnesium

Product 1

HCID 54081156HCID 54081156, compoundYield 98.8%

Reagents, catalysts & solvents 2

HCID 313Hydrochloric AcidSolventHCID 8028TetrahydrofuranSolvent3×

Procedure

The alcohol required for the preparation of the pyrethroid is prepared as follows: ##STR12## A reaction vessel is charged with 14.6 g of magnesium filings together with a trace of iodine crystals. 73.6 g of ethyl bromide in 25 ml of tetrahydrofuran are then added dropwise such that the tetrahydrofuran boils gently under reflux. The Grignard solution formed is added dropwise at 0°-5° C. to a solution of 62.1 g of phenylacetylene in 250 ml of tetrahydrofuran and the mixture is stirred until the evolution of gas ceases. The resultant solution is cooled to 0° C. and 99 g of 3-phenoxybenzaldehyde are added dropwise such that the temperature does no exceed +5° C. The reaction mixture is stirred overnight at room temperature and then cooled to a temperature in the range from 0° to +5° C. About 100 g of ice are added, whereupon a precipitate forms which is dissolved in 100 ml of concentrated HCl. The aqueous solution is extracted with three 150 ml portions of ether and the extracts are washed with NaHCO3 solution and then dried over Na2SO4. The ether is distilled off by rotary evaporation, affording as residue 148 g of 3-phenoxy-α-phenylethynylbenzyl alcohol with a refractive index of nD23 =1.6238 and with an NMR spectrum as shown in FIG. 2. The yield is 98.8 % of theory.

Workup

  1. customis prepared
  2. temperatureunder reflux
  3. customThe Grignard solution formed
  4. customdoes no exceed +5° C
  5. stirringThe reaction mixture is stirred overnight at room temperature
  6. temperaturecooled to a temperature in the range from 0° to +5° C
  7. extractionThe aqueous solution is extracted with three 150 ml portions of ether
  8. washthe extracts are washed with NaHCO3 solution
  9. dry with materialdried over Na2SO4
  10. distillationThe ether is distilled off by rotary evaporation

Sources & evidence

ORD record
ord-6464c132216645fd9620abafe7c23352
Source dataset
uspto-grants-1987_07
Patent number
US04681593

Reaction notes

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