Methyl chloroformate → tert.-butyl(1R,cis)2,2-dimethyl-3-[2-(methoxy carbonyl)-ethynyl]-cyclopropane-carboxylate
反応式
[CH3:1][C:2]1([CH3:16])[C@@H:4]([CH:5]=[C:6](Br)Br)[C@H:3]1[C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10].C([Li])CCC.Cl[C:23]([O:25][CH3:26])=[O:24].P(O)(O)([O-])=O.[Na+]>C1CCCCC1.O1CCCC1>[CH3:1][C:2]1([CH3:16])[C@@H:4]([C:5]#[C:6][C:23]([O:25][CH3:26])=[O:24])[C@H:3]1[C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10]参加物
反応物 4
生成物 1
試薬・触媒・溶媒 2
反応条件
- 温度
- -70 °C
実験手順
55 g of tert-butyl(1R,cis)2,2-dimethyl-3-(2,2-dibromovinyl)-cyclopropane-carboxylate were introduced into 550 cm3 of tetrahydrofuran and the mixture was cooled to -70° C. 132 cm3 of a 20% solution of butyllithium in cyclohexane were added over 40 minutes to the mixture which was stirred for 30 minutes at -65° C. 12.5 cm3 of methyl chloroformate were then added thereto and after 2 hours reaction at -70° C., the temperature was allowed to rise again to -20° C. The mixture was poured into an aqueous solution of monosodium phosphate and the mixture was extracted with ether. The organic phase was washed, dried and evaporated to dryness under reduced pressure. 38.3 g of the residue were chromatographed over silica gel and was eluted with an 8-2 cyclohexane-ethyl acetate mixture to obtain 17.2 g of tert.-butyl(1R,cis)2,2-dimethyl-3-[2-(methoxy carbonyl)-ethynyl]-cyclopropane-carboxylate.
後処理
- customafter 2 hours reaction at -70° C.
- customto rise again to -20° C
- extractionthe mixture was extracted with ether
- washThe organic phase was washed
- customdried
- customevaporated to dryness under reduced pressure
- custom38.3 g of the residue were chromatographed over silica gel
- washwas eluted with an 8-2 cyclohexane-ethyl acetate mixture
出典と根拠
- ORDレコード
- ord-041ef04e3009439f83e17c73be2b2c6d
- 出典データセット
- uspto-grants-1985_10
- 特許番号
- US04547522
反応ノート
読み込み中…