• Relative acidity

• $H_2O>ROH>RC \equiv CH>H_2>NH_3>RH$

• all alcohols except methanol are weaker acids than water

• Basicity order

• $CH_3O^-

• Electronic effect R

• Extent of solvation of conjugate base

(A) Reactions replacing H atom $1^o>2^o>3^o$

• (1) With active metals $(Na, K, Al, Mg)$

• $2ROH+2Na \rightarrow 2RONa+H_2 \uparrow$

• $ROH+M \rightarrow RO^-M^+ \frac{1}{2}H_2 \uparrow$

• (2) With grignard’s reagents react with active hydrogen

• $ROH (stronger \hspace{1mm} acids) +R’MgX \rightarrow R’H+ROMgX$

(3) with organic acids in presence of conc $H_2SO_4$- esters

(4) With acid chloride or anhydride $(RCOCl or (RCO)_2O))$ $\rightarrow$ ester

(5) With phosphoric acid

(6) OH $\rightarrow$ good leaving group

• With alkane/arene sulfonyl chloride

• $RSO_2Cl$

• $ArSO_2Cl$

• $RSO_2Cl$ methane sulfonyl chloride $\rightarrow$ mesylates methane sulfonate ester

• $CF_3SO_2Cl \rightarrow$ triflates

• $ArSO_2Cl PTSCl \rightarrow$ tosylates

• $R-\ddot O_{..}H+ClSO_2R’ \xrightarrow [{-psyr HCl}]{Pry} ROSO_2R’+HCl$

• Reaction

• Reactions replacing OH group

• With halogen acids HI-(temperature below HI)HBr-(conc HBr or KBr/NaBr + $H_2SO_4 \rightarrow$ nylux) HCl-(conc HCl+anhydrous$ZnCl_2$ lewis acids $\rightarrow$ heat)

• Substitution reaction $\rightarrow$ acid catalyzed

• $R-OH + HX \rightarrow RX + H_2O$

• prommates OH, makes it a good leaving group

• Reaction

• $3^o>2^o>1^o$

• $1^o$, $CH_3CH_2CH_2CH_2CH_2OH(n-pentyl \hspace{1mm} alcohol) \xrightarrow [{anhydrous ZnCl_2, \Delta}]{HCl} CH_3CH_2CH_2CH_2CH_2Cl$(n-pentyl chlorids)

• $2^o$, $>-OH( isopropylalcohol) \xrightarrow [{NaBr,H_2SO_4,reflux}]{conc HBr or} >-Br$

• $3^o$, $t-butylalcohol \xrightarrow [{RT}]{conc HCl}$ t-butyl chloride

(2) With phosphorus halides $(PCl_5,PBr_3, P/I_3, P/Br) \rightarrow$ allyl halides

• Reaction

• Reaction

• $1^o$ or $2^o$ alcohals

• no carbocation formation

• no rearrangement especially at/ under $0^oC$

• $PBr_3$ preferred reagent food alkyl bromide fomation

(3) With thionyl chloride $\rightarrow$ allyl chloride

• $ROH+SOCl_2 \xrightarrow {pyr} RCl+ SO_2(g)\uparrow+HCl(gases)\uparrow$

(C) Reactions involving both R and OH groups

• Oxidation, dehydro generation, dehydration

• OXIDATION of alcohols

• a number of oxidizing agents

• ($1^o \rightarrow$ $2^o \rightarrow$ $3^o) \rightarrow$

• OXIDATION of alcohols

• Mn (VII) and Ge(VI)

• Mn(VII) $KMnO_4 \rightarrow$ acidified $KMnO_4$, alkaline $KMnO_4$

• $1^o \rightarrow$ acid

• $RCH_2OH \xrightarrow {KMnO_4} R-COOM$

• Reaction

• No loss of C atoms

• $R-CH_2OH \xrightarrow [{KMnO_4,OH^-,H_2O, \Delta}]{basic aq.} R-COO^-K^+ \xrightarrow {H^+} RCOOH+MnO_2\downarrow$brown ppt

• Cr(VI) $\rightarrow CrO_3/dil H_2SO_4$ in aq acetone chromic acid $H_2CrO_4$

• Reaction

• Jones reagent

• $H_2CrO_4$ or $Na_2Cr_2O_7$ in $H_2SO_4$ water

• $RCH_2OH(1^o), Cr_2O_7^{2-}$(orange red)

• $R-CH=O+Cr^{2+} \xrightarrow {Cr_2O_7^{2-}} RCOOH$

• Mechanism of oxidation $1^o ROH \rightarrow$ old acid

• Reaction