10-1 Alcohols & Thiols & Ethers Sources Structure, Nomenclature, Properties Acidity and Basicity Rx with active metals Conversion to R-X, inorganic acid halides Rxs with HX S N 1/S N 2, sulfonates Dehydration of alcohols Oxidation of 1 o and 2 o alcohols Oxidation of glycols [Pinacol & Thiols/Sulfur chemistry - skip] 6, 31, ss34 Chapter 10 Chapter 11

10-2 Chapter 10 reactions acid base active metal substitution oxidation sources nomenclature (alcohol & ethers) properties

10-3 Preparation of alcohols - (review)

10-4 Chapter 10 sources nomenclature (alcohol & ethers) properties reactions acid base active metal substitution oxidation

10-5 Nomenclature alcohols & ethers IUPAC names – alcohol sp 3 C-OH -longest chain that contains the -OH = root -OH gp lowest number - suffix -e to -ol ether R-O-R’ sp 3 C, sp 2 C, spC in R & R’ bonded to O -always subsituent - #-prefix, alkoxy (special ethers #,#-epoxy) 1-ethoxy-2-butanol

10-6 Epoxides special ethers Nomenclature - #,#-epoxy (substituent) or oxirane #,#-epoxy-#-pentyn-#-ol (4S)-4,5-epoxy-2-pentyn-1-ol ether acetylene alcohol

10-7 Nomenclature-Alcohols IUPAC names Longest chain that contains the -OH = root Give -OH group lowest number Change suffix -e to -ol (S)-2-methyl-1-butanol

10-8 oxygen sp 3 Structure - Alcohols Alcohol functional group: -OH group bonded to an sp 3 hybridized carbon bond angles ~ 109.5° CO H H H 3 C H

10-9 Physical Properties Hydrogen bonding: H bonded to an electronegative atom (F, O, or N) etc. R O H O H R O H R O H R Hydrogen bond weak (~ 5 kcal/mol)

10-10 Physical Properties ethanol & dimethyl ether - constitutional isomers but weak hydrogen bonds have dramatic effects: hydrogen bonds no hydrogen bonds

10-11 Quiz Name:___________________________ seat:_____ Write a reaction equation that represents one of the source of alcohols.

10-12 Reactions alcohols: acid base indirect substitution indirect  -elimination active metals oxidation ethers: base indirect substitution indirect  -elimination epoxides: substitution, indirect & direct

10-13 Acidity of Alcohols weak acids conjugate bases strong

10-14 Acidity of Alcohols RSH 8.5

10-15 Acidity of Alcohols Acidity  on: stabilization and solvation electron donation destabilize alkoxides decreases solvation

10-16 Alcohols + Li, Na, K (active metals) form metal alkoxides metal alkoxide sodium methoxide alcohols rx with metals

10-17 rx with metals sodium cyclohexoxide

10-18 basicity of alcohols/ethers weak Lewis base (water-like) R = H or alkyl oxonium ion

° alcohols (ethers) react very rapidly with HCl, HBr, HI. Alcohols/Ethers indirect Substitution ( with HX) 1°alcohols/ethers are unreactive under these conditions R = H or alkyl

° alcohols + HBr (or HI ) racemization, rearrangement, olefins indirect Substitution ( with HX)

o or 3 o ROH/ROR’ with HX - S N 1 -H + +X - [-HOR] good leaving group racemization, rearrangement, olefins R = H or alkyl

o ROH/ROR’ with HI or HBr - S N 2 X (-) displace R’ = H or alkyl

10-23 indirect Substitution (with SOCl 2 )

10-24 indirect Substitution (with PBr 3 ) 2 nd ROH to RBr 3 rd ROH to RBr

10-25 indirect Substitution R= H, alkyl R’= H, alkyl; X= Br, I

10-26 alcohols - alkyl sulfonates, good Lgp

10-27 alkyl sulfonates (sulfonate ester) S S S R good leaving group for Sn2 rx DMF

10-28 rx: alkyl sulfonates prep:

10-29 rx: alkyl sulfonates prep:

° alcohols (ethers) with H 2 SO 4 or H 3 PO 4 dehydration of ROH/[-HOR’] of ROR’ 2° alcohols (ethers) 3° alcohols (ethers) R = H or alkyl

10-31 Dehydration of ROH (-OR of ethers) Mechanism - same forward or reverse. alkene addition and  -elimination compete

10-32 Pinacol Rearrangement This section out [rearrangement under dehydration conditions]

10-33 Chapter 10 sources nomenclature properties reactions acid base active metal substitution oxidation

10-34 Oxidation

10-35 Oxidation: 1° ROH Pyridinium chlorochromate (PCC): pyridine + CrO 3 [Cr(VI)] + HCl PCC converts 1° alcohols to aldehydes and 2 o alcohols to ketones

10-36 Oxidation aldehyde acid ketone NR (no reaction)

10-37  -elimination of H and chromate +

10-38 Oxidation: 1° ROH hydrate

10-39 Oxidation 1 o and 2 o ROH K 2 Cr 2 O 7 and many other reagents

10-40 Oxidation of Glycols with H 5 IO 6 (or HIO 4 2H 2 O) acyclic or cis-1,2 cyclic diols

10-41 Oxidation of Glycols with H 5 IO 6 (or HIO 4 2H 2 O) 11

10-42 OsO 4 / HIO 4 equivalent to O 3 /red. source of diols

10-43 mechanism Oxidation of Glycols with H 5 IO 6 (or HIO 4 2H 2 O)

10-44 Oxidation of Glycols with H 5 IO 6 (or HIO 4 2H 2 O) 10

10-45 Oxidation of Glycols with H 5 IO 6 (or HIO 4 2H 2 O) 10

10-46 How does one make butanal from 1-bromobutane?

10-47 What else can be made using the chemistry of chapters 3, 6, 7, 8, 9, 10, 11 & “15”?

10-48 Chapter 15 future chapter chemistry

10-49 Chapter 10 sources nomenclature properties reactions acid base active metal substitution oxidation Chapter 11/15