Ethyl Acetate → 17,17-Bis-(ethylenedioxy)-13-(cis-2-chlorovinyl)-10-methyl-gon-5-ene

HRID 972268Notes

Reaction equation

HRID 972268 reaction equation
C([Li])CCC.[Cl-].[Cl:7][CH2:8][P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[CH2:28]1[CH2:42][O:41][C:36]23[O:37][CH2:38][CH2:39][O:40][C:30]2([C@:31]2([CH2:55][CH2:54][C@H:53]4[C@@H:43]([CH2:44][CH:45]=[C:46]5[C@:51]4([CH3:52])[CH2:50][CH2:49][CH2:48][CH2:47]5)[C@@H:34]2[CH2:35]3)[CH:32]=O)[O:29]1.C(OCC)(=O)C>CCCCCC.O1CCCC1.N1CCCCC1>[CH2:39]1[CH2:38][O:37][C:55]23[O:41][CH2:42][CH2:28][O:29][C:30]4([C@:31]2(/[CH:32]=[CH:8]\[Cl:7])[C@H:34]([C@@H:43]2[CH2:44][CH:45]=[C:46]5[C@:51]([CH3:52])([CH2:50][CH2:49][CH2:48][CH2:47]5)[C@H:53]2[CH2:54]3)[CH2:35][CH2:36]4)[O:40]1

Participants

8

Reactant 4

HCID 8857Ethyl AcetateHCID 197823(Chloromethyl)triphenylphosphonium chlorideHCID 8673512317,17-Bis-(ethylenedioxy)-androst-5-en-18-alHCID 178418339Butyllithium

Product 1

HCID 8673512217,17-Bis-(ethylenedioxy)-13-(cis-2-chlorovinyl)-10-methyl-gon-5-ene

Reagents, catalysts & solvents 3

HCID 8028TetrahydrofuranSolvent2×HCID 8058HexaneSolventHCID 8082PiperidineSolvent

Procedure

8.4 ml of a 1.56 molar solution of butyl-lithium in hexane is added to a suspension of 5.82 g of chloromethyltriphenyl-phosphonium chloride in 107 ml of absolute tetrahydrofurane and 1.67 ml of piperidine at 0° C, under argon and with complete exclusion of moisture. After 30 minutes, 1.3 g of 3,3:17,17-bis-(ethylenedioxy)-androst-5-en-18-al in 22.5 ml of tetrahydrofurane are added dropwise at room temperature. Thereafter, the mixture is stirred for 1 hour at room temperature and then poured into ice water. Ethyl acetate is added to the mixture and the organic phase is separated off and washed with cold 1 N hydrochloric acid, with water, with sodium bicarbonate solution and with saturated sodium chloride solution. After drying over sodium sulphate and evaporating the solvent, the residue is chromatographed on silica gel using a mixture of hexane/ethyl acetate (9:1). 3,3;17,17-Bis-(ethylenedioxy)-13-(cis-2-chlorovinyl)-10-methyl-gon-5-ene is isolated from the first fractions and is recrystallised from methylene chloride/hexane; melting point 172°-174° C, [α]D 25 = -81°. The corresponding trans isomer is obtained from the later fractions and after recrystallisation from petroleum ether melts at 108°-110° C, and has an [α]D25 = -52°.

Workup

  1. customthe organic phase is separated off
  2. washwashed with cold 1 N hydrochloric acid, with water, with sodium bicarbonate solution and with saturated sodium chloride solution
  3. dry with materialAfter drying over sodium sulphate
  4. customevaporating the solvent
  5. customthe residue is chromatographed on silica gel using
  6. additiona mixture of hexane/ethyl acetate (9:1)

Sources & evidence

ORD record
ord-b84356c327424cc6a1f76f2cd23b5ea9
Source dataset
uspto-grants-1977_10
Patent number
US04052421

Reaction notes

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