alcohols - SUMMARY General Infomation Synthesis of Alcohols...

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Unformatted text preview: SUMMARY General Infomation Synthesis of Alcohols 0 From Alkenes via Oxymercuration-Demercuration ' From Alkenes via Hydroboration-Oxidation - From Alkenes via Hydroxylation with 0504 0 From Aldehydestctones via Reduction with NaBH4 - From Carbonyl Compounds via a Grignard Reaction ' From Esters via Reduction with LiAlH4 Reactions of Alcohols 0 Preparation of Alkencs via Acid-Catalyzed Dehydration O Preparation of Alkyl Halides from 3° Alcohols ' Preparation of Alkyl Halides from 1° and 2° Alcohols 0 Preparation of Aldehydcs/Ketones from 1° and 2° Alcohols Alcohols 1 Alcohols 2 Alcohols 3 Alcohols 4 Alcohols 5 Alcohols 6 Alcohols 7 Alcohols 8 Alcohols 9 Alcohols 10 Alcohols 11 Alcohols GENERAL INFORMATION Alcohols 1 Alcohols (R—OH) Introduction: Alcohols are compounds with a hydroxyl group {—OH) as their main functional group. They are rather abun- dant in nature and widely used in the chemical industry. Some common alcohols are listed below: 1. Ethanol is produced from fermentation of sugar by yeast (e.g., beer). It is also industrially synthesized from ethylene. 2.. Isopropyl alcohol, commonly known as rubbing alcohol, is prepared from propene. It has antibacterial properties. Physical Properties: 0 Alcohols have higher melting and boiling points than alkanes of comparable molecular weight because of their ability to form intermolecular hydrogen bonds. ' Only low-molecular—weight alcohols (fewer than 5 carbons) are soluble in water. Chemical Properties: 0 The bond angle formed by C—O—H is slightly less than 109.5°. The hydroxyl group is SP3 hybridized and has tetrahedral geometry. 0 Alcohols have both very weak acid (pKa ranges from 16 to 19) and very weak base properties. 1. An increase in alkyl substitution results in decreased acidity because bulkier groups sterically hinder water from stabilizing RO‘ (e.g., methanol is more acidic than tert—butyl alcohol). 2. An increase in halogen substitution results in increased acidity because halogens are electron-withdrawing and can stabilize the negative charge on RO‘ {this is known as the inductive effect). ' Alcohols react vigorously with veryostrong bases (e.g., NaH, NaNHZ), alkali metals, and Grignard reagents, but less so with hydroxide, to yield alkoxide ions. However, they do not react withcweak bases such as amines and HCO3‘. Nomenclature: Alcohols can be named in a similar manner as alkanes but with two differences: (1) the last —e of the alkane is replaced with -01, and (2) the —OH is assigned the lowest possible number on the carbon chain. or: me a on —(|2H —cHa UH 3-Methy172ibutanol Spectroscopy: H NMR: Hydrogen attached to the carbon atom has a characteristic peak at 8 = 3.5 ppm. Hydrogen attached to the oxygen atom has a characteristic peak at 2—8 ppm. C NMR: Characteristic peak at 8 = 60 ppm for carbon-bearing OH group. IR.- The hydroxyl group {—OH) has characteristic absorption in the range 3300—3600 cm_1. (\3 2-6 ppm (usuaIly broad) H— —OH z—n—q a 3.5-4.5 ppm U SYNTHESIS OF ALCOHOLS Alcohols 2 FROM ALKENES VIA OXYMERCURATION—DEMERCURATION H36 H CH3 H H 1) Hg(0Ac1-),H20 H H H H 2) NaBHi-fOH OH H Propene 2—Propano! (alkene) (alcohol) EH; 1. The regiochemistry of this complex reaction obeys Markovnikov’s rule: The —OH group attaches to the more substituted carbon (the one with fewer H atoms), while the —H attaches to the less substituted carbon (the one with more H atoms}. 2. This reaction has two steps: oxymercuration and demercuration (see Mechanism). 3. The first step of the reaction proceeds through a mercurinium ion intermediate. 4. The -OH on the product comes from H20; the —H comes from sodium borohydride (NaBH4). Note: A direct hydration reaction also exiSts but is used only in the industrial synthesis of alcohols; poor yields occur in laboratory synthesis. Hac H 0 CH3 H 1) “JP 4 H H H H 2) H20 0” H Propene 27Propanol (alkene) (alcohol) 7 o This reaction proceeds through a carbocation intermediate. Faster hydration reactions are observed with more stable carbocations. Mechanism: I. Oxymercuration 1. Electrophilic addition of mercuric acetate R [Hg(OAC)2] to the alkene yields a mer— curiniurn ion. Note that mercury is bonded to both carbon atoms. 2. Nucleophilic attack by H20 on the more substituted carbon atom of the mercurinium ion occurs (Markovuikov addition step). 3. Free acetate {‘OAc) abstracts a proton from the newly substituted H20 to produce an organomercury compound. Alkene II. Demercuration 4. The organomercury compound reacts with sodium borohydride (NaBH4} to produce the final alcohol product. OHH 71“ NaBH R H 3—4,, H HgOAc Organomercury compound H HFéH Hg 70A: Crime Mercuric acetate OHH H H Alcohol :§H2 at H ® H EH'sQ9 H OAc Mercurinium ion HOAc + H Hg DAG Organomercury compound SYNTHESIS OF ALCOHOLS Alcohols 3 FROM ALKENES VIA HYDROBORATION—OXIDATION H , H H OH \ / 1) 3H5. THF | l /C = C\ fi—> “\NC —C~,,fl "ac H 2) 1-1203. ‘OH, H10 H 1 \ H HQC H Propene ] Propane] [alkene) (alcohol) Keys: 1. The regiochernistry of this reaction is opposite Markovnikov’s rule. The —OH group attaches to the less substituted carbon (the one with more H atoms), while the —H attaches to the more substituted carbon. This is partly due to steric hindrance effects (see Mechanism). 2. Syn addition of the —OH and —H groups is observed (i.e., b0th groups are attached to carbon atoms on the same side of the double bond). . The reaction proceeds thru alkylborane intermediates (see Mechanism). . The reaction has two stages: hydroboration and oxidation (see Mechanism). The hydroboration stage leads to a trialkylborane product which subsequently undergoes oxidation to form the desired alcohol. #96 Mechanism: l. Hydroboration 1. For both steric and electronic reasons, the electrophile (boron) adds to the less substituted carbon, while the more nucleophilic atom (hydrogen) adds to the more substituted carbon of the double bond. 2. The reaction occurs Via a cyclic transition state, which results in syn addition of the B and H atoms (both on the same side of the double bond}. An alkylborane intermediate is formed. 3. This monoalkylborane reacts with two more alkene molecules to form a trialkylborane product. 11. Oxidation 4. Hydroperoxide anion (HOO‘), which is formed from hydrogen peroxide (H202) in basic solution, attaches readily to the boron of the trialkylborane. 5. A rearrangement occurs, which shifts an alkyl group of the trialkylborane from the boron to the oxy- gen and expels a hydroxyl group. 6. Repetition of steps 4 and 5 occurs until a trialkylborate ester is formed. 7. Hydrolysis of the trialkylborate ester yields 3 mol of the desired alcohol product and one B{Ol-I)4f molecule. .. 3 R H R 5+ H R H Hog: CHZCHZH \ / (1'; \ / (g) \ / @ k l CZC —> H—C'L'C—H —> H—C—C—H 4} B /‘) D ‘ " l l “3% RCH CH/ \CH CHR H H i - 2 2 2 2 HiBH 3' H""BH2 H 3“: Cyclic Alkylborane Trialkylbotane transition stale ® 7 enzcnzn _ cnzcuzn ® 6) ‘ C5} 6' 3 RCHzCHzOH OH I ("CH2CH20)3B EOE—l ?— CHQCHZR {7 RCHZCHz — $ — CHZCHZH .1 7 7 _ + “OH” Trialkylborate ester OCHZCHin of} OH Rearrangement SYNTHESIS OF ALCOHOLS Alcohols 4 FROM ALKENES VIA HYDROXYLATION WITH 0504 (OR KMnO4) "ac H _ I Hall: H \ / l) 0304, pyrldme \ / C = C —> “\C -C.v,, \ I H/ \H 2)NaHS()3,H2CI H“/ \"H HO OH Propene cr's— l .Z-Diol (alkene) (alcohol) Keys: 1. This reaction generates high yields of cis-diols. 2. Syn addition of the —OH groups is observed (i.e., both groups are attached to carbon atoms on the same side of the double bond). 3. This reaction proceeds through a cyclic osmate intermediate ( see Mechanism). Note: Potassium permanganate (KMnO4) is another reagent used to oxidize alkenes. As with 0804, syn addition is observed, a cyclic manganate intermediate is formed, and cis-diols are produced (albeit in lower yields). HaC H HJC H H3C H \c c/ 1) KMTIQ: \c C/ H20 \c C/ = ——)- \\ — I; —> \\ — I H/ \H 2) NaOH. H20 H“? \w’“ "‘“7 O\ /O HO OH Propene / Mn\\ cis— 1 .Z-Diol (alkene) 0— 0 (alcohol) Cyclic manganate intermediate 7-. Mechanism: 1. Syn addition of 0504 to the alkene yields a cyclic osmate intermediate. 2. Bisulfite ion (HSO3‘) reduces the cyclic osmate intermediate to generate the cis-diol. It should be noted that if KMnO4 is used instead, bisulfite is not required because of the rapid hydrolysis of the manganate intermediate. R n- n n' _ 3 Fl‘ \6 c/ 1)0504 \c c/ 2)HSO3 \c c/ = —> 4r o\ /0 HO OH Alkene [/03 \ cisiDiol \0 (alcohol) Cyclic osmale intermediate SYNTHESIS OF ALCOHOLS Alcohols 5 FROM ALDEHYDES/KETONES VIA REDUCTION WHH NaBH4 0 OH 0 OH II NaBl—h I ll NaBI—I4 | CHa—C—H —> GHQ—67H CHa—C—CH3 —> CH3~C70H3 CH3OH | CH3OH I H H Ethanal Ethanol Acetone 2—P1'0panol (aldehyde) (1° alcohol) (ketone) (2° alcohol) Keys: 1. Sodium borohydride (NaBH4) rapidly reduces both aldehydes and ketones. 2. Reduction of aldehydes yields 1° alcohols, whereas reduction of ketones yields 2” alcohols. 3. In this reaction, NaBH4 acts as a source of hydride ion (H?) which does not exiSt as a discrete species in solution. It should be noted that NaBH4 adds its hydride on the carbonyl carbon and not on the carbonyl oxygen. Note: An acidic workup is not required because the carbonyl oxygen abstracts a proton from the alcoholic solvent (see Mechanism). 4. Stoichiometry: One mole of borohydride ion reduces four carbonyl groups to alcohols. Note- Lithium aluminum hydride (LiAlH4, LAH) is another, much more reactive, reducing agent. Unlike NaBH4 reactions, LAH reactions are run in ether and require an acidic workup. Many functional groups (e.g., esters, amides, acyl halides, and alkyl halides} are readily reduced by LAH but not by NaBH4. Although more reac- tive, LAH can still be used in the reduction of 0L,|3-unsaturated ketones to unsaturated alcohols: Note that if NaBH4 is used instead, a mixture of saturated and unsaturated alcohols will be generated. See Alcohols 7 for additional reactions in which LAH is used as a reducing agent. 0 OH ll 1) LiAlH4 fEt10 l CH3—C—CH=CH—CH3 ———> CHawCiCH=CHiCH3 2) H30+ | H (LB-Unsaturated Unsaturated (allylic) ketone alcohol Mechanism: Exact details of the mechanism are complex. Briefly, NaBH4 [the equivalent of the nucleophilie hydride ion (H:_)], attacks the carbonyl carbon of the aldehyde (or ketone), while at the same time the carbonyl oxygen atom abstracts a protou from the alcoholic solvent {e.g., CH3OH), thereby producing an alcohol. H, ° l '|| 6 /¢i‘."\/3H3 —> /E|:—H + CH305H3 R 2 H H z Aldehyde: Z = H Ketone: Z:alkyl OCHJ on H SYNTHESIS OF ALCOHOLS Alcohols 6 FROM CARBONYL COMPOUNDS VIAA GRIGNARD REACTION 0 OH ‘ RMUX = Gngnard reagent 2 M ,l, R =calkyl, aryl. Vinyl / \ 2)H30+ l X=c1.Br,1 R Carbonyl compound Alcohol Keys: 1. This is a nucleophilic addition reaction in which the Grignard is the nucleophile. It is a reaction that is widely used to extend a carbon chain. 2. Depending on the starting carbonyl compound, different types of alcohols can be generated. Starting Carbonyl Compound Alcohol Product Formaldehyde 1° Alcohol Aldehyde 2° Alcohol Kctone 3° Alcohol Ester 3" Alcohol 3. In order to fully convert an ester to 3 3° alcohol, two moles of Grignard reagent are needed to react with one mole of ester. 4. Of all the carbonyl compounds, only carboxylic acids do not react with Grignard reagents to produce alco- hols because the Grignard reagentsare destroyed in the reaction. Note: 1. Preparation of the Grignard reagent (see Alley! Hall‘des 4 for more details}. a 0 OH II lst 11'ng II 2nd R‘ng ll Rmcoocm ———#_> CH30MgX + Fl—C—Fl' —> R—c—R' I H. Ester Methoxymagnesium Ketone 3° Alcohol halide Beware: Grignard reagents cannot be formed if the reacting alkyl halide also contains another functional group (specifically a ketone, alcohol, carboxylic acid, or amine). 2. Since it is chemically Similar to the Grignard reagent, an organolithium (RLi) can also be used to convert carbonyl Compounds to alcohols (see Alkyl Halides 5 for the synthesis of RLi). Mechanism: 1. The R group of the Grignard reagent is nucleophilic; it attacks the carbonyl carbon to form a tetrahedral alkoxide. 2. The negatively charged oxygen abstracts a proton from a hydronium ion (H30+) to form the alcohol prod- uct with a longer carbon chain. ng T H t3 Gear‘s—H ?/ C CD -— C — ® _ c i / L\ I I e (.3 Fl R Carbonyl R "9* Tetrahedral Alcohol compound intermediate 0 SYNTHESIS OF ALCOHOLS r Alcohols 7 FROM ESTERS VIA REDUCTION WITH L£A1H4 O OH ll 1) LiAll-{ri‘ other | CH3CH2 —C—0—CH3 ———> CHacHz—C*H + CHgoH 2) H30‘ I H Methyl propranoate l—Propanol Methanol (ester) (1° alcohol) Keys: 1. LiAlH4 is the preferred choice for ester reduction because reaction with NaBH4 is too slow. NaBH4 can be used to reduce aldehydes and ketones While leaving esters unchanged. 2. The reaction forms two alcohols: The carbonyl group yields a 1° alcohol, while the —OR group yields ROH (see Mechanism). . Two moles of LiAlH4 reduce one mole of ester. . In this reaction, LiAlH4 acts as a source of hydride ion (Hz—l, which does not exist as a discrete species in solution. Note: Reduction of other carbonyl compounds via LiAlH4 o H 1) LiAll-h [ether n —C—0H fl ncnzon _ y 2) H30“ Carboxylic flClCl 1° Alcohol 0 0 II 1) LiAu-u/cther " ‘ Fl — C — Cl ——)- FIGHon 2] HJO+ Acid chloride 1° Alcohol l l L'Al th ' n —c— o—c—H Lime—er» 2 FICHgOH 2) [430* Acid anhydride 1° Alcohol Mechanism: 1. The hydride ion (H?) from LiAlH4 nucleophilically attacks the carbonyl carbon of the ester to form a tetrahedral anion intermediate. 2. This intermediate then expels an aikoxide ion FOR), giving an aldehyde. 3. The aldehyde is reduced by a second hydride ion (from LiAlH4) to form the alkoxide of the 1° alcohol. 4. Alkoxide ions are neutralized by added acid (i.e., acid workup} to form the alcohols. Note that the alkyl groups (R and R1) of the ester are not changed. L|+ G, a" 09 L'* OH I1 l ’ 3x I I H 0+ 1 -+ FI'—'C/H —C~J—> n'g-C—H _3_> R|_c_H l" e Li+ | | G) ‘ (ii in.“ $9 “"3 Ald ri1 d H H e e 0 . R—T/H L 37%.." (g) y l Alcohol °\ (0\ Li" eon ——>"30+ HOH H H @ Ester Tetrahedral Alkoxide Alcohol anion expelled intermediate REACTIONS OF ALCOHOLS Alcohols 8 PREPARATION OF ALKENES VIA ACID-CATALYZED DEHYDRATION CH3 CH; CH I 1) [race H1804 El / ‘1 CH3CHZCH2 ——C— CH; ——> CH5CH26H2 —C—CH3 + CHJCHgi CHE C l 2) heat \CH CH " Q-Methyl—Z—pentanol 2-Methyl-1—pentene 2-Methy172epentene (3" alcohol) (minor product} (major product) Keys: 1. Dehydration of 2° and 3° alcohols, but not 1° alcohols proceeds via an E1 mechanism (see Alkyl Halides .9 for details on E1). 2. The reaction involves a carbocation intermediate. Because 3“ carbocations are the most stable, 3" alcohols are the most reactive and readily produce alkenes. The following rule is handy: Alcohol: 1° << 2° < 3° Reactivity: Least 2:) Most Only 2° and 3° alcohols are reactive enough to form alkenes. Under similar conditions, 1° alcohols form ethers instead. However, under conditions of stronger acidity and higher temperatures, 1“ alcohols can yield alkenes via an E2 mechanism (see Alley! Halides 8 for details on E2). 3. The reaction may yield a mixture of alkenes. If it does, the most substituted alkene is the major product (Zaitsev’s rule). [In the example above, 2-methyl-2—pentene is the major product, while 2~methyl-1-pentene (the less substituted alkene} is the minor product] Reasons: (3) The transition state for the formation of the more substituted alkene has a lower activation energy, and therefore it forms faster. (b) In the presence of acid, the less substituted alkene may isomerize to the more substituted, more stable, alkene. 4. This reaction is catalyzed by strong acid (e.g., H2504). r o Mechanism: 1. 2. 3. The oxygen on the alcohol abstracts a proton from the acid (e.g., H2504) to form a protonated alcohol. Spontaneous loss of H20 from the protonated alcohol yields a carbocation intermediate. It should be noted that this is the rate-limiting step. A base (e.g., bisulfate ion) abstracts a proton from the carbocation intermediate, thereby forming an alkene and regenerating the acid catalyst. The more substituted alkene forms faster because of a lower energy of activation. . The alkenes produced in step 3 may also isomerize to form the more substituted, more stable alkene as the major product (a step not shown in the figure}. H' R' H' H R. H CH —(|:—CH —R CH Atlz—CH —R ® CH —E|:—(l:—R Ki)» \ — / 3 2 3 2 f4) 3 L /C — C\ + H2504 ‘CIDH Q... 6 IL me n fl @ ‘ H20 '2 an A1 h 1 K+H — OSOaH H @0503” osoan ‘ c0 0 Protonated alcohol Carboeation Alkene intermediate REACTIONS OF ALCOHOLS Alcohols 9 PREPARATION OF ALKYL HALIDES FROM 3° ALCOHOLS CH3 CH3 HBr | CHg—C—CHa fi——> CHg—c—CHJ l H20 | OH Elr 2-Methy1—2-propanol 2-Bromn—2-methylpropane (3° alcohol) (alkyl halide) Keys: 1. This is a good reaction for converting 3° alcohols to alkyl halides. Primary and secondary alcohols do not work well here (refer to Alcohols 10 for reactions involving 1" and 2° alcohols). 2. The reaction proceeds through an 5N1 mechanism (see Alley] Halides 7 for more details on 5N1). Mechanism: 1. The oxygen on the alcohol abstracts a proton from the hydrogen halide (HX). 2. Spontaneous loss of H20 from the protonated alcohol yields a carbocation intermediate. This is the rate- limiting step. 3. The nucleophilic halide ion (1— > Br' > Cl‘) reacts with the carbocation to produce an alkyl halide. R' FI‘ R‘ R' l W i i l Ric—Fl" -r®—> R—C—R" %} R’C’R" i)- R—C—FI" l (’I 33 l :9H @0H H20 X 39 Alcohol L” I}; J. " Hydrogen Halide ion Alkyl halide halide REACTIONS OF ALCOHOLS Alcohols 10 PREPARATION OF ALKYL HALIDES FROM 1° AND 2° ALCOHOLS PB cmcnzcnzcnzon —”> CHacHZCHZCHzBr l-Butanol l-Bromobutane (1° alcohol) (10 alkyl bromide) Lets; 1. The reaction proceeds through an 5N2 mechanism (see Alley! Halides 6 for more details on 8N2). 2. This is a good reaction for converting 1° and 2° alcohols to alkyl halides. Tertiary alcohols do not work well in this reaction (refer to Alcohols 9 for the reaction involving 3" alcohols.) 3. Phosphorus tribromide (PBr3) is exclusively used with 1° and 2° alcohols (but not with 3" alcohols) to make the hydroxyl group a better leaving group (see Mechanism). 4. One mole of PBr3 converts 3mol of ROH t0 3 mol of RBr (see Mechanism). Note: PBr3 is specifically used for the production of alkyl bromides. If an alkyl chloride is desired instead, SOCIZ should be used as the reagent. This reaction also proceeds through an 5N2 mechanism. SOCl cuatmztmcn-i3 —-2—> CH3CH2CHCH3 + $0; + H6! l Pyridine I OH Cl l-Butanol 2-Chlorobutane (2° alcohol) (2” alkyl chloride) 0 Mechanism: 1. The alcohol reacts with PBr3, thereby transforming the —OH from a poor to a better leaving group (HOPBrZ). 2. A nucleophilic bromide ion attacks the carbon from the back and expels the leaving group (HOPBrz), forming the alkyl bromide product. It should be noted that the stereochemistry of the product is inverted (e.g., from the R configuration in the starting material to an S configuration in the product). 3. The HOPBrZ formed reacts with two more alcohol molecules by a similar mechanism, ultimately yielding P(OH)3 and three alkyl bromide molecules for each PBr3 used {a step not shown in the figure). FI' R' R' (I: L c PB [email protected]> (I: HOPE N“ .. 6‘“ ('9 r2 ' ' “’11 4' '2 H\ I \OH H\ 1 Q0/ uwerston Bl./ \ IH R n e R I R zamcoml Br_P_Br 3;: H 2° Aikyl bromide (in REACTIONS OF ALCOHOLS Alcohols 11 PREPARATION OF ALDEHYDES/KETONES FROM 1° AND 2° ALCOHOLS 0 OH 0 FCC I NagCI’gOT CchchchHon fir CchHzcnch CHJCH2CHCH3 —+> CH3CH2CCH3 CH2C|2 H30 l-Butanol Butanal 2-Butanol Z-Butanone (1° alcohol) (solvent) (aldehyde) (2° alcohol) (ketone) Keys: 1. The reaction proceeds through an EZ-like oxidationi'reduction reaction of a preformed chromate ester (see Mechanism for more details). 2. This is a good reaction for converting 1° alcohols to aldehydes and converting 2" alcohols to ketones. Tertiary alcohols cannot undergo this reaction, as there is no ot—hydrogen atom. 33. Conversion of 1° alcohols to aldehydes: 1. Depending on the oxidizing reagent, 1" alcohols can be converted to aldehydes or further oxidized to form carboxylic acids (see Note for 1° alcohol to carboxylic acid oxidation). 1" alcohols —> aldehydes A carboxylic acids ii. Pyridinium chlorochromate (PCC, CSHSNCrO3Cl) in an organic solvent (CHZClz) is the preferred oxidizing reagent. Reason: Oxidation of 1° alcohols to aldehydes in aqueous solution would proceed further to yield carboxylic acids (see Note). 3b. Conversion of 2° alcohols to ketones: The preferred reagent is sodium dichromate (NaZCr207) or chromic acid (HZCrO4) in aqueous acid solution. Note: . Primary alcohols are usually converted to carboxylic acids with aqueous solutions of these chromium reagents (tag, NaZCr207, H2Cr04). O N32010:: || CHacHzcflzcflon —+> CHaCHQCHchH H30 leButanol Butanoic acid (1° alcohol) (carboxylic acid) Mechanism: 1. The chromium-based oxidizing agent reacts with the alcohol to yield a chromate ester intermediate. 2. A base (e.g., H20, pyridine) abstracts a proton from the chromate intermediate, eliminating (and reducing) the Cr and generating an aldehyde 0r ketone. It should be noted that 3" alcohols cannot be oxidized because they lack the ot-hydrogen necessary for this elimination reaction. 2 o z o z l ll 6) i ll ® | R—l'f—OH + X—(flr—X —> H—ETODCEII—X —> R—C=D Ho: 0 H 0 alcohol Pyridine Ltflase gldflhyd; ngfll _ et : = Z = H, 1“ alcohol X — OH’ Cl Chromate ester one y 2 = alkyl, 2° alcohol _ intermediate ...
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This note was uploaded on 09/13/2009 for the course CHEM 12-636 taught by Professor Hubbard during the Spring '09 term at UGA.

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alcohols - SUMMARY General Infomation Synthesis of Alcohols...

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