• By pyridinium chlorochromate(PCC)

• $CrO_3$ dissolve in $HCl \xrightarrow {Treatment \hspace{1mm} with \hspace{1mm} Py}$ PCC $\rightarrow CH_2Cl_2$ solvent

• Dehydrogenation$\rightarrow$ Removal of $H_2$

• $1^o$ $RCH_2OH \xrightarrow [{-H_2}]{Cu/300^oC} RCHO$

• $2^o$ $R_2CHOH \xrightarrow [{Cu/300^oC}]{-H_2} R_2CO+H_2 \uparrow$

• $3^o$ $R_3C-OH \rightarrow R_2C=CH_2+H_2O$

• $R=>CH_3$

• (Removal of $9-H_2O$)

• (i) Chemical

• (ii) Catalytic

• Reaction

• $- \overset {|}{\underset{\underset {H} {|}}{C}}-\overset {|}{\underset{\underset {OH} {|}}{C}}- \xrightarrow [{conc. H_3PO_4, \Delta}]{conc H_2SO_4} -\overset{|}{C}=\overset{|}{C}-+H_2O$

• Elimination reaction- rearrangement $(E_1)$ $\hspace{2mm}$ $\rightarrow -\overset{+}{\underset{|}{C}}-$

• Reactivity $3^o>2^o>1^o$ alcohols

• $CH_3CH_2CH_2CH_2OH \xrightarrow [{\Delta E_1, -H_2O}]{conc H_2SO_4} CH_3CH_2CH=CH_2+CH_3CH=CH-CH_3$ (Major)

• $C_6H_5-\overset {\overset {CH_3}{|}}{\underset{\underset {CH_3} {|}}{C-OH}}-\xrightarrow [{-H_2O, \Delta}]{H_2SO_4} C_6H_5-\overset{\overset{CH_3}|}{C}={CH_2}$

• Catalytic $\rightarrow Al_2O_3$ at $350^oC$ pass vapours of alcohol over alumina

• Iodoform

• $CH_3-\overset {\overset {O}{||}}{C}-$ $\quad$(alyl)

• $CH_3 -\overset {\overset {O}{||}}{C}-R$ $\rightarrow$ Methyl Ketones

• $CH_3-\overset {\overset {H}{|}}{\underset{\underset {OH} {|}}{C}}-R$ $\hspace{3mm}$ secondary alcohol $\rightarrow CH_3-\underset {\underset {O}{||}}{C}-{R}$

• $CH_3-\overset {\overset {H}{|}}{\underset{\underset {OH} {|}}{C}}-H$ $\hspace{3mm}$ primary alcohol $\rightarrow CH_3-\underset {\underset {O}{||}}{C}-{H}$

• $CH_3 -\overset {\overset {O}{||}}{C}-H$ $\hspace{3mm}$ only aldehyde

• Compound + $X_2$/alkali $\rightarrow$ halo form

• Compound + $Cl_2 \rightarrow$ chloroform (colorless)

• Compound + $Br_2 \rightarrow$ bromoform (pale yellow)

• Compound + $I_2 \rightarrow$ iodoform (pale yellow)

(i) Oxidation

(ii) Halogenation

(iii) Hydrolysis

• $CH_3-\overset {|}{\underset {\underset {OH}{|}}{C}}-$

• $CH_3 -\overset {\overset {O}{||}}{C}-R$

• $2NaOH+Cl_2 \rightarrow NaOCl+NaCl+H_2O$

• Ethanol

1. $CH_3CH_2OH+X_2+2NaOH \rightarrow CH_3CHO+2NaX+2H_2O$

2. $CH_3CHO+3X_2+3NaOH \rightarrow CX_3.CHO+3NaX+3H_2$

3. $CX_3.CHO+NaOH \rightarrow CHX_3(Haloform)+HCOONa$

• Overall reaction $CH_3CH_2OH+4X_2+6NaOH \rightarrow CHX_3+HCOONa+5NaX+5H_2O$

• $CH_3-\overset {\overset {O}{||}}{C}-$ $\rightarrow$ Methyl Ketone

1. $CH_3-\overset {\overset {O}{||}}{C}-R+3X_2+3NaOH \rightarrow CX_3-\overset {\overset {O}{||}}{C}-R+3NaX+3H_2O$

2. $CX_3-\overset {\overset {O}{||}}{C}-R +NaOH \rightarrow CHX_3+ R-\overset {\overset {O}{||}}{C}-O-Na$

• Overall reaction $CH_3COR+3X_2+4NaOH \rightarrow CHX_3+RCOONa+3NaX+3H_2O$

• Application

(a) Distinguish ketone / alcohol $CH_3-\overset{\overset{O}{||}}{C}-$

(b) $CHCl_3, CHBr_3,CHI_3$

• $CH_3-\overset{\overset{O}{||}}{C}-OH \xrightarrow {Iodoform}$$\times$ yellow ppt.

• $CH_3-\overset{\overset{O}{||}}{C}-NH_2 \rightarrow$ $\times$

• $CH_3-\overset{\overset{O}{||}}{C}-OCH_3 \rightarrow$ $\times$

• Acid & acid derivatives don’t give positive iodoform reaction

• Glycols are dihydric alcohols $C_nH_{2n}(OH)_2$

(I) From alkenes $\rightarrow$

(a) aq. or alkaline $KMnO_4 \rightarrow$

(b) $OSO_4$

(c) Epoxide / Hydrolysis

(d) Hypohalous acid follow by hydrolysis

(II) From alkyl halides

(a) hydrolysis with carbonate solution

(3) From alkylens diamine Treatment with nitrous acid

(4) Reduction of various carbonyl compounds “electrolytic red”

• Reactions of Glycols

(a) due to -O-H group

(b) due to R & OH group

1. Action with sodium metal $\rightarrow$ monosodium disodium salt

(2) with acids - monoester & diester

(3) with acetic - anhydride acetylation

• $2CH_2OH \xrightarrow [{Py}]{(CH_2CO)_2O} 2CH_2-O-\overset{\overset{O}{||}}{C}-CH_3$

(4) With halogen acids

(a) HCl or HBr

• $2CH_2OH \xrightarrow [{160^oC,-H_2O}]{HCl} HOH_2C-CH_2Cl \xrightarrow [{200^oC,-H_2O}]{HCl} 2CH_2Cl$

(b) with $HI/PI_3$

• $2CH_2OH \xrightarrow [{-2H_2O}]{+2HI} 2CH_2I \xrightarrow {-I_2} \overset {\overset {CH_2}{=}}{CH_2}$

(5) with nitric acid

• $2CH_2OH +2HONO_2 \rightarrow 2CH_2ONO_2+2H_2O$

(6) With $PCl_5, PBr_3$

• $2CH_2OH \xrightarrow{PCl_5} 2CH_2Cl$

(7) with aldehydes & Ketones acetals and ketals cyclic compounds

(9) Dehydration $\rightarrow$ (a) heat (b) $ZnCl_2$ anhydrous (c) $H_3PO_4$ (d) conc $H_2SO_4$

(a) $2CH_2OH \xrightarrow[{500^oC}]{\Delta} (CH_2)_2O(epoxide) +H_2O$

(b) $2CH_2OH \xrightarrow[{\Delta, -H_2O}]{ZnCl_2} H_2C=CHOH(vinyl \hspace{1mm} alcohol) \rightarrow H_3C-CHO$ ( acetaldehyde)

(c) $2CH_2OH \xrightarrow [{-H_2O}]{H_3PO_4} HOH_2C-CH_2-O-CH_2-CH_2OH$ (diethylene glycol)

(d) $2CH_2OH \xrightarrow[{-2H_2O, \Delta}]{conc. H_2SO_4} 2(CH_2-O-CH_2)$ (dioxane)