Term
| reagents and product of epoxidation of alkenes reaction |
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Definition
1. E-stilbene [LIMITING]
2. 3-chloroperbenzoic acid
=>
E-stilbene oxide
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Term
| solvent in epoxidation reaction |
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Definition
CHCl3
- low boiling point, so don't overheat it |
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Term
| what class of reaction is epoxidation? |
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Definition
| oxidation/reduction reaction |
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Term
| is the epoxidation of alkenes an exo/endo reaction? A syn or trans addition? |
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Definition
| ENDOTHERMIC reaction; SYN addition |
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Term
| in epoxidation, in which layer is the stilbene oxide found? |
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Definition
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Term
| what work-up do you perform in epoxidation? |
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Definition
| add NaOH to react with the 3-chloroperbenzoic acid and send it to the aqueous phase. |
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Term
| what is used to recrystallize in the epoxidation reaction? |
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Definition
| methanol (hot at first, then cooled) |
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Term
| what mechanism happens in the dehydration of 2-methylcyclohexanol? |
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Definition
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Term
| what is the major product in the dehydration of 2-methycyclohexanol and why? |
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Definition
| - 1-methylcyclohexene, because the double bond is more highly substituted (Zeitsev product) |
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Term
| what is the NMR signal for the major and minor products of the dehydration of 2-methylcyclohexanol? |
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Definition
1-methylcyclohexene: ONE signal
3-methylcyclohexene: TWO signals |
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Term
| what are the reagents and the products of the dehydration reaction? |
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Definition
1. 2-methylcyclohexanol
2. phosphoric acid
=>
1-methylcyclohexene
3-methylcyclohexene |
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Term
| in the dehydration of 1-methylcyclohexanol, why is phosphoric acid used instead of sulfuric acid? |
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Definition
| sulfuric acid will oxidize the alcohol. |
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Term
| what are the two types of GC columns? |
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Definition
1. capillary, which has better separation and a shorter analysis time
2. tubular (packed)
- WCOT, which has liquid coating the surface
- SCOT, which has a solid coating the surface |
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Term
| what did we use for our (nonpolar) stationary phase? |
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Definition
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Term
| raising the temperature in GC will have what effect on retention time, flow rate, and separation? |
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Definition
| retention time will go DOWN, flow rate will go UP, and separation will be less good |
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Term
| two types of GC detector: |
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Definition
flame-ionizing (used with capillary)
thermal conductivity
both of these convert the substances to electrical signals |
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Term
| in dehydration of 2-methylcyclohexane, which layer is the organic layer? |
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Definition
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Term
| what do the GC results of the dehydration reaction look like? |
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Definition
| two peaks; product is NONPOLAR; 1-methylcyclohexene will have the later, larger peak |
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Term
| what is used to remove the phosphoric acid from the dehydration product? |
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Definition
| NaOH; together they end up in the BOTTOM layer, with the organic layer being on top |
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Term
| what is special about the way we conducted our oxidation of cyclohexene experiment? |
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Definition
| green chemistry! we did the experiment microscale and used as few chlorinated reagents as possible |
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Term
| what are the reactants in the oxidation of cyclohexene? |
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Definition
1. H2O2 (oxidizing agent)
2. Na2WO4 (catalyst)
3. aliquat 336 (phase transfer agent) |
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Term
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Definition
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Term
| in the oxidation of cyclohexene, what boiling control did we use? |
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Definition
| magnetic stirrer (NOT boiling stone/stick) |
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Term
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Definition
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Term
| friedel-crafts alkylation uses what reagants? |
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Definition
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Term
| FC-alkylation can't be performed with ____________ groups which ___________ the ring |
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Definition
| electron withdrawing groups which DEACTIVATE the ring. |
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Term
| what is the ratio of alcohol to dimethoxybenzene in the FC alkylation? |
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Definition
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Term
| NMR spectrum for FC alkylation product and reactant |
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Definition
product: 3 singlets with a 9:3:1 ratio with aromatic being the most deshielded.
reactant: two peaks |
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Term
| what is the SOLVENT for FC alkylation? |
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Definition
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Term
| what is the recrystallizing solvent used in FC alkylation? |
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Definition
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Term
|
Definition
| silicon with four methyl groups |
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Term
| what are the two different reagents you make into semicarbazones? |
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Definition
cyclohexanone (kinetic control)
furaldehyde (thermodynamic control) |
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