Methyl acetoacetate → 6-Methyl-5-hepten-2-one

HRID 1105990Notes

Reaction equation

HRID 1105990 reaction equation
[CH3:1][C:2]([OH:16])([CH2:5][CH2:6][CH2:7][CH:8]([CH3:15])[CH2:9][CH2:10][CH2:11][CH:12]([CH3:14])[CH3:13])[CH:3]=[CH2:4].[CH3:17][C:18]([OH:22])(C)[CH:19]=C.C(OC)(=O)CC(C)=O>>[CH3:1][C:2]([CH2:5][CH2:6][CH2:7][CH:8]([CH3:15])[CH2:9][CH2:10][CH2:11][CH:12]([CH3:14])[CH3:13])=[CH:3][CH2:4][CH2:17][C:18](=[O:22])[CH3:19].[CH3:9][C:8](=[CH:7][CH2:6][CH2:5][C:2](=[O:16])[CH3:1])[CH3:15]

Participants

5

Reactant 3

HCID 7757Methyl acetoacetateHCID 82572-Methyl-3-buten-2-ol2×HCID 5288243,7,11-Trimethyldodec-1-en-3-ol

Product 2

HCID 98626-Methyl-5-hepten-2-oneHCID 534359106,10,14-Trimethyl-5-pentadecen-2-one

Conditions

Temperature
165 °C

Procedure

A mixture of 637 g of 3,7,11-trimethyl-dodec-1-en-3-ol (86% pure), 8.6 g of Al isopropylate and 60 g of 3-methyl-but-1-en-3-ol was heated to 165° C. in the apparatus described in Example 12, and 471 g of methyl acetoacetate and 159 g of 3-methyl-but-1-en-3-ol were added dropwise in the course of 5 hours, whilst keeping the temperature at the 2nd theoretical plate of the column at about 90°-100° C. by appropriate adjustment of the reflux ratio. After a further 2 hours' reaction at 165° C., the mixture was worked up by distillation. 598 g of 6,10,14-trimethyl-pentadec-5-en-2-one and 161 g of 2-methyl-hept-2-en-6-one were obtained.

Workup

  1. additionwere added dropwise in the course of 5 hours
  2. customat about 90°-100° C.
  3. customAfter a further 2 hours' reaction at 165° C.
  4. distillationthe mixture was worked up by distillation

Sources & evidence

ORD record
ord-7d81119d8c724f3c8c38f5f9a8197db3
Source dataset
uspto-grants-1982_01
Patent number
US04310705

Reaction notes

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