Purpose:
Toisolateterpenesfoundinpinetreeoleoresinwithminimaldecomposition,andanalyzethe
collectedresidue.
RequiredMaterials:
§ Pinetreeoleoresin(PTO)
§ Condenser
§ Stillhead
§ Thermometer
§ Heatingmantle
§ Boilingchips
§ Round-bottomflask
§ Glasswool
§ Seperatoryfunnel
§ Graduatedcylinder
§ Diethylether(OEt2)
§ Hexanes
§ Dichloromethane(CH2Cl2)
§ Anhydroussodiumsulfate(Na2SO4(s))
§ SaturatedNaClsolution
Procedure:
1. PlacePTOinahotwaterbath(toliquefyandeasemanipulation)
2. PourdesiredmassofwarmPTOintoround-bottomflask.
3. Add75mLdistilledwaterforeverygramofPTOadded
4. Addseveralboilingchips(moreshouldbeaddedoverthecourseofthedistillationto
preventbumping).
Assembleapparatusasdepictedin
5. Figure1.Notethattheround-bottomflaskshouldbewrappedinglasswooltominimize
heatdissipationintotheair.
Figure1
6. Refluxfor30min.
7. Re-assembleapparatusasdepictedinFigure2.
8. Collectdistillatefor1hrpergramofPTOadded.(Theresultingdistillateshouldbe
cloudywater,orclearwaterwithsmalldropletsfloatingontop).Thethermometer
shouldreadslightlybelow100°C(96-98).
9. Aftersufficienttimeanddistillateiscollected,extractthedistillateusingaseperatory
funnelaccordingtothefollowingscheme:
a. Approximately10mLOEt2per40mLdistillate,twice.
b. Approximately20mLHexanesper40mLdistillate,twice.
c. Approximately20mLCH2Cl2per40mLdistillate,twice.
Figure2
10. Combineallorganiclayers,andthenwashwith20mLsat.NaCl(aq)usingaseperatory
funnel.
11. DryorganiclayerusinganhydrousNa2SO4(s),thenfilteroffthesolidmatter.
12. Gentlyevaporatetodryness,eitherbylowheatingorbyusingarotaryevaporator(note
thatthesolventshaveverylowboilingpoints,sonotmuchheatisrequired).
13. Apine-smellingresidueshouldbeobtained(theyieldlikelydependentonmany
differentvariables).
14. Collectasmallquantityoftheresidue,dilutex20usingCH2Cl2.Thissamplecanbe
analyzedwithGC/MSusingthefollowingparameters:
a. WeusedaSLB-5msfusedsilicacapillarycolumn,30mx0.25mmi.d.,film
thickness0.25micrometeres.Thecolumntemperaturestartedat70°C,and
increasedat2°C/minto200°C.Thecarriergas,Helium,wasdeliveredat1.70
mL/min(splitratiois1:10).Electronionizationmassspectrometrywasusedin
ordertoidentifyterpenesbytheirfragmentationpatterns.