Citraconic Anhydrides → 3-Methylbicyclo[4.2.0]oct-1(6)-ene-3,4,-Dicarboxylic Anhydride

HRID 1742713

反応式

HRID 1742713 の反応式
[C:1]1(=[O:8])[O:7][C:5](=[O:6])[CH:4]=[C:2]1[CH3:3].[CH2:9]=[C:10]1[CH2:13][CH2:12][C:11]1=[CH2:14]>ClCCl>[CH3:3][C:2]12[C:1](=[O:8])[O:7][C:5](=[O:6])[CH:4]1[CH2:14][C:11]1[CH2:12][CH2:13][C:10]=1[CH2:9]2

参加物

4

反応物 2

HCID 12012Citraconic Anhydrides2 回HCID 139725Cyclobutane, 1,2-bis(methylene)-

生成物 1

HCID 536806403-Methylbicyclo[4.2.0]oct-1(6)-ene-3,4,-Dicarboxylic Anhydride

試薬・触媒・溶媒 1

HCID 6344Dichloromethane溶媒

実験手順

Into a 500-mL, single-neck round bottom glass flask containing a magnetic stirring bar was weighed 96.62 grams (0.862 moles) of citraconic anhydride. The flask was then fitted with a three-neck adapter to which was attached a thermometer, a condenser and a 250-mL addition funnel. To the funnel was added 86.0 grams of a distilled dimethylenecyclobutane (DMCB) cut containing 90.2% (by GC) 1,2-isomer (77.6 grams, or 0.968 moles, of 1,2-dimethylenecyclobutane). The flask was purged with dry nitrogen. The DMCB was then added dropwise to the citraconic anhydride with stirring. No temperature increase due to reaction exotherm was evident. When the DMCB addition was complete, the mixture was allowed to stand for 53 days at room temperature to complete the reaction. At the end of this period, gas chromatography revealed that the peak corresponding to unreacted citraconic anhydride had essentially disappeared. The product was then dissolved in dichloromethane and filtered to remove insoluble gelatinous material. Dichloromethane and unreacted volatiles were removed at 60° C. on a rotary evaporator to yield a crystalline product. The crude yield was 156.18 grams (94%). 152 g of product was then recrystallized from 165 grams of cyclohexane with strong stirring. Yield of recrystallized MBODA was 132.17 grams (80%). Melting point was 64°-68° C. The 1H and 13C NMR spectra of the product were consistent with the following structure; no impurities were seen in the product by NMR except for a small amount of cyclohexane. ##STR6##

後処理

  1. additionInto a 500-mL, single-neck round bottom glass flask containing a magnetic stirring bar
  2. customThe flask was then fitted with a three-neck adapter to which
  3. additiona condenser and a 250-mL addition funnel
  4. customThe flask was purged with dry nitrogen
  5. additionThe DMCB was then added dropwise to the citraconic anhydride
  6. temperatureNo temperature increase due to reaction exotherm
  7. additionWhen the DMCB addition
  8. customthe reaction
  9. filtrationfiltered
  10. customto remove insoluble gelatinous material
  11. customDichloromethane and unreacted volatiles were removed at 60° C. on a rotary evaporator
  12. customto yield a crystalline product
  13. custom152 g of product was then recrystallized from 165 grams of cyclohexane with strong stirring

出典と根拠

ORDレコード
ord-8231e12c60164893981b329bd4b48687
出典データセット
uspto-grants-1994_08
特許番号
US05340890

関連ノート

読み込み中…