formaldehyde - Sciencemadness Dot Org

2-', I FORMALDEHYDE
lleilione Is ^ tautomeric compound as shown by the keto and enol forms
indicated in the structural lonuutrir .=?hov. - n below:
H
O
!
J
c
HC OK
)zC C— -OH
c
O
V
i.
C
/ \
H^C CH
1. ¥
\ /
C
OH
O
r i.
C
/ \
I \
(CH3)2C C=0
\ /
G
H*
OjS^Dimethyldihydroresorcinoi -5\5-Diniethylcyclohexanedione-S ,a
It is a colorless to slightly yellow crystalline compound melting at 148-
130 C C, somewhat sparingly soluble in -water but readily soluble in alcohol
and acetone. Its solubility iu water at various temperatures 53 is shown
below:
Teroperj.ture Solubility
= C GT3TH5 Methone per 100 cc Soluti^
19 0.401
25 0.416
50 1.185
SO 3.020
90 3.S37
Methone reacts with alkali as a monobasic acid and may be titrated with
standard alkali, using phenolphthalein as an indicator.
Formaldehyde and methone react quantitatively in neutral, alkaline, or
mildly acidic aqueous or alcoholic solutions to form methylene bis-methone,
as indicated in the following equation:
H
O
I
C
# \
H—C CH
| II + CHftO{aq) >
(CH3)aC C—OH
\ /
C H H
H3 O O
I I
c c
# \ H£ / \
H—C C——C • - C C—H
1 II li [ -1- H*G
(CHS) 2C C—OH HO—G C (CH2) s
\ / \ /
c c
H5
H*