Synthesis of diacylals of amino-substituted aldehydes

Full text of DOI:10.1134/S1070363211070310

ISSN 1070-3632, Russian Journal of General Chemistry, 2011, Vol. 81, No. 7, pp. 1570–1571. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © M.B. Gazizov, R.A. Khairullin, A.I. Alekhina, A.A. Bashkirtsev, 2011, published in Zhurnal Obshchei Khimii, 2011, Vol. 81, No. 7,
pp. 1223–1224.
LETTERS
TO THE EDITOR
Synthesis of Diacylals of Amino-Substituted Aldehydes
M. B. Gazizov, R. A. Khairullin, A. I. Alekhina, and A. A. Bashkirtsev
Kazan State Technological University, ul. K. Marksa 68, Kazan, Tatarstan, 420015 Russia
e-mail: mukattisg@mail.ru
Received February 28, 2011
DOI: 10.1134/S1070363211070310
It is known that the reaction of aldehydes and carbo-
xylic acid anhydrides affording diacylals (1,1-dialkano-
ates) occurs only in the presence of acid catalysts BF3
and PСl3 [1].
disappearance of the aldehyde proton signal at δ 10
ppm in the H NMR spectrum of the reaction mixture.
1
After the removal of volatile substances the residue
was distilled to give diacylals IIIa–IIIb as individual
compounds. Product IIIc is a thick liquid non-distil-
lable in a vacuum. It was identified as a quaternary
ammonium salt IV (Scheme 2).
We first found that dialkylamino-substituted al-
dehydes I react with carboxylic acids anhydrides II
under mild conditions without any catalyst.
R12NCH2CMe2CHO + (R2CO)2O
To a solution of the compound IIIc in acetonitrile
was added dropwise a slight excess of methyl iodide at
room temperature under stirring. After 6 h the solvent
and volatiles were removed, the residue was re-
crystallized from ethanol.
I
II
→ R12NCH2CMe2CH(OCOR2)2
III
III, R1 = R2 = Me (а), R1 = Me, R2 = Et (b), R1 = Me, R2 =
Ph (c), R1 = Et, R2 = Me (d).
3-(Dimethylamino)-2,2-dimethylpropane-1,1-
diethanoate (IIIа). A mixture of 5 g (0.038 mol) of 3-
(dimethylamino)-2,2-dimethylpropanal Iа and 3.95 g
(0.038 mol) of acetic anhydride was kept in a sealed
ampule for 14 days and then distilled in vacuum. Yield
8 g (54%), bp 51–52ºС (0.065 mm Hg), nD20 1.4336. 1Н
NMR spectrum (acetone-d6), δ, ppm: 0.8 s (6H,
CMe2), 1.93 s (6H, COMe), 2.07 s (2H, CH2N), 2.17 s
Obviously, the starting aldehyde I with tertiary
amine moiety acts as a nucleophilic catalyst B
(Scheme 1).
An equimolar mixture of compounds I and II was
kept at room temperature for two weeks till the
Scheme 1.
R2
C
(R2CO)2O
1
1
O−
O−
O
R2NCH2CMe2CH
I + B
R2NCH2CMe2CH
B+
B+
O
COR2
−OCOR2
R2NCH2CMe2CHOCOR2
1
III + B
B+
Scheme 2.
Me2NCH2CMe2CH(OCOPh)2 + MeI → I– Me3N+CH2CMe2CH(OCOPh)2
IV
1570

1571
SYNTHESIS OF DIACYLALS OF AMINO-SUBSTITUTED ALDEHYDES
(6H, NMe2), 6.5 s (1H, CH). Found N, %: 6.17.
C11H21NO4. Calculated N, %: 6.06.
3-(Diethylamino)-2,2-dimethylpropane-1,1-di-
ethanoate (IIId) was obtained from 5 g (0.032 mol) of
Ib and 3.25 g (0.032 mol) of acetic anhydride. Yield
4.7 g (57%), bp 72–73ºС (0.01 mm Hg), nD20 1.4368.
1Н NMR spectrum (acetone-d6), δ, ppm: 0.8 s (6H,
3-(Dimethylamino)-2,2-dimethylpropane-1,1-di-
propanoate (IIIb) was obtained from 5 g (0.038 mol)
of Iа and 5.04 g (0.038 mol) of propionic anhydride.
Yield 6.3 g (62.7%), bp 73–74°С (0.082 mm Hg), nD20
1.4352. 1Н NMR spectrum (acetone-d6), δ, ppm: 6.55 s
(1Н, СН), 2.15 s (2H, CH2N), 2.70 s (6Н, NMe2), 2.10
3
CMe2), 0.91 t (6H, NCH2Me, JHH 6.75 Hz), 1.93 s
(6H, COMe), 2.07 s (2H, CH2N), 2.5 q (4H, NCH2Me,
3JHH 6.75 Hz), 6.5 s (1H, CH). Found N, %: 6.22.
C13H25NO4. Calculated N, %: 5.93.
3
q (4Н, СОСН2, JHH 7 Hz), 0.90 t (6Н, СОСН2CН3,
3JНH 7 Hz), 0.80 s (6H, CMe2). Found N, %: 6.02.
The Н NMR spectra were registered on a Tesla
1
C13H25NO4. Calculated N, %: 5.93.
BS-567A spectrometer operating at 100 MHz, internal
reference TMS. The 31Р NMR spectra were recorded
on a RYa-2303 instrument (21 MHz) relative to 85%
Н3РО4.
3-(Dimethylamino)-2,2-dimethylpropane-1,1-di-
benzoate (IIIc) was obtained from 5 g (0.038 mol) of
Iа and 8.76 g (0.038 mol) of benzoic anhydride. Yield
12.66 g (92%). Ammonium salt of IIIc was obtained
as follows. To a solution of 12.36 g (0.035 mol) of
compound IIIc in 35 ml of anhydrous acetonitrile was
added dropwise 5.93 g (0.042 mol) of methyl iodide at
room temperature. The mixture was stirred at 25ºС for
6 h. Yield 17.1 g (93.5%), mp 124–125ºС (ethanol). 1Н
NMR spectrum (CDCl3), δ, ppm: 1.5 s (6H, CMe2), 3.7
s (9H, NMe3), 4.08 s (2H, CH2N), 7.41 s (1H, CH),
7.15–8.1 m (10H, Ph). Found N, %: 6.22. C13H25NO4.
Calculated N, %: 5.93.
ACKNOWLEDGMENTS
This work was financially supported by the Federal
Target Program “Research and Scientific-Pedagogical
Personnel of Innovative Russia for 2009–2013” (contract
no. P-1108).
REFERENCES
1. Kochhar, S.K., Bal, B.S., Deshpande, R.P., Rajadhyak-
sha, S.N., and Pinnick H.W., J. Org. Chem., 1983,
vol. 48, p. 1765.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 7 2011