Synthesis of imides and amides from diacetyl-l-tartaric acid anhydride

Article abstract of DOI:10.2174/157017810791130649

Diacetyl-L-tartaric acid anhydride reacted with aromatic primary amines to yield imides (3g-l) and amides (4a- f). The ortho-substituted aromatic primary amines either with electron donating or withdrawing groups yielded amides, whereas para-substituted amines produced imides. However, meta-substituted aromatic primary amines with electron withdrawing residues afforded amides while electron donating counterparts furnished imides.

Full text of DOI:10.2174/157017810791130649

Letters in Organic Chemistry, 2010, 7, 319-322
319
Synthesis of Imides and Amides from Diacetyl-L-Tartaric Acid Anhydride
Sara Naz1, Javid H. Zaidi*,1, Tahir Mehmood1, Sher Wali1, Muhammad Ali2, Muhammad Taha2 and
Khalid M. Khan*,2
1Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan
2H. E. J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of
Karachi, Karachi-75270, Pakistan
Received August 12, 2008: Revised February 13, 2010: Accepted February 18, 2010
Abstract: Diacetyl-L-tartaric acid anhydride reacted with aromatic primary amines to yield imides (3g-l) and amides (4a-
f). The ortho-substituted aromatic primary amines either with electron donating or withdrawing groups yielded amides,
whereas para-substituted amines produced imides. However, meta-substituted aromatic primary amines with electron
withdrawing residues afforded amides while electron donating counterparts furnished imides.
Keywords: Diacetyl-L-tartaric acid anhydride, aromatic primary amines, imides, amides.
INTRODUCTION
involve the reaction of anhydride with primary amines.
Various other methods were also reported for the synthesis
of amides involving the reaction of isocyanides with acids
[14], Ugi reaction [15] (from aldehydes and primary amines),
Schmidt reaction [16] (from ketones and ammonia),
Schotten-Baumann reaction [17] (from acyl halides and
primary amines).
Imides are classically defined as cyclic secondary amides
of the dicarboxylic acids with wide range of applications [1].
The interest in structural characterization of cyclic imides is
most frequently attributed to the biological importance of
some of their naturally abundant analogues [2]. N-
Substituted imides exhibited a variety of biological activities
such as antimicrobial [3], antiepileptic [4], anticonvulsive
[5], and antifungal [6]. Maleimides are an important class of
substrates for various pharmacological and chemical
applications. In pharmacological applications, maleimides
are used as chemical probes for protein structures [7], as
immunoconjugates for cancer therapy as well as for the
production of antibiotics [8]. They are also used as analogues
for cyclic tetra-peptide chlamydocin [9], photoactivatable
fluorescence derivatives [6] and as new herbicides and
pesticides [10]. Among other uses, imides are utilized in the
production of polyimides, which are necessary materials for
a variety of purposes including their use in the electronics
and space craft industry [6].
RESULTS AND DISCUSSION
In our continuation of studies towards the development
of new routes for the synthesis of organic compounds [18],
we herein report a facile synthesis of imides and amides by
using diacetyl-L-tartaric acid anhydride and substituted
primary aromatic amines (Scheme 1). All the synthesized
compounds were purified by column chromatography and
characterized by using spectroscopic techniques like 1H- and
13C-NMR spectroscopy, mass and elemental analysis.
In our studies we found that the steric as well as
electronic factors determine the formation of amides or
imides. Ortho-substituted aromatic primary amines only give
amides irrespective of the nature of substituent which
suggests that once the amide is formed the steric hindrance
offered by the ortho-substituent prevents the ring closure to
yield the imide. On the other hand when the same substituent
is at the para- position they exclusively gave imides as
product which supports our argument given above.
Surprisingly, in case of meta-substituted primary aromatic
amines, amides and imides, both, are formed depending
upon the nature of substituents. Primary aromatic amines
having electron donating groups yield exclusively imides,
while, amines with electron withdrawing groups afforded
amides only. The difference in the nucleophilicity of amino
group may be rationalized on electronic and steric factors,
respectively.
Amides also possess a variety of biological activities, for
example, paracetamol is a potent non-steroidal anti-
inflammatory (NSAID) and antipyretic drug having an
amide moiety. Analgesic properties of paracetamol were
discovered accidentally when a similar molecule, acetanilide,
was serendipitously found to possess analgesic as well as
antipyretic properties, and was quickly introduced into
medical practice under the name of Antifebrin [11].
Different methods have been reported for the synthesis of
imides including solid phase synthesis [12], solution phase
and microwave synthesis [13]. Most of these methods
*Address correspondence to these authors at the Department of Chemistry,
Quaid-i-Azam University, Islamabad, Pakistan; Tel: 0092-51-90642107;
Fax: 0092-51-90642241; E-mail: javid_zaidi@yahoo.com
Synthesis of some imides and amides was carried out by
using diacetyl-L-(+)-tartaric acid anhydride with primary
amines (Scheme 1). All the synthesized compounds were
H. E. J. Research Institute of Chemistry, International Center for Chemical
and Biological Sciences, University of Karachi, Karachi-75270, Pakistan;
Tel: 0092-21-4824910; Fax: 0092-21-4819018, 0092-21-4819019;
E-mail: hassaan2@super.net.pk
1570-1786/10 $55.00+.00
© 2010 Bentham Science Publishers Ltd.

320 Letters in Organic Chemistry, 2010, Vol. 7, No. 4
Naz et al.
OH
O
O
O
AcO
AcO
AcO
AcO
AcO
O
O
CH3COOH
reflux, 1 h
NR
R-NH2
O
AcO
O
HN
1
2 (a-l)
R
3 (g-l)
S. No.
4 (a-f)
S. No.
R
Yield (%)
R
Yield (%)
3g
3h
3i
3-CH3C6H4-
4-OHC6H4-
4-COOHC6H4
4-NO2C6H4
4-OCH3C6H4
4-CH3C6H4
68
75
65
79
76
73
4a
4b
4c
4d
4e
4f
2-OHC6H4
68
75
71
80
70
55
2-COOHC6H4
2-NO2C6H4
3j
2-OCH3C6H4
2-CH3C6H4
3k
3l
3-COOHC6H4
Scheme 1. Synthesis of imides and amides.
purified by column chromatography and characterized by
using spectroscopic techniques like 1H- and 13C NMR
spectroscopy, mass and elemental analysis.
(m, 4H), 6.39 (s, 2H), 2.63 (s, 6H); 13C-NMR (75 MHz,
CDCl3): ꢀ 178.9 (-COOR), 170.1 (-CON), 156.3-116.6
(C6H4), 72.8 (-CH-), 20.4 (CH3-CO); Anal. Calcd. for
C14H13O7N: C, 54.32; H, 4.26; N, 4.55. Found: C, 53.95; H,
4.51; N, 4.46.
EXPERIMENTAL GENERAL
4-(3,4-Diacetoxy-2,5-dioxopyrrolidine-1-yl) Benzoic Acid
(3i)
All the synthesized compounds were characterized by IR,
1H-NMR, 13C-NMR spectral data, mass spectrometry and
elemental analysis. IR spectra (KBr) were recorded on a
Yield: 65%, solid, M.p. = 127-129 ºC; IR (KBr): 3500-
2677 (O-H) 2955 (C-H stretching), 1735 (CO imide),1730
1
Schimadzu FT-IR 270 spectrophotometer. H-NMR spectra
1
(CO acid) 1703 (CO ester), 1609 (aromatic) cm-1; H-NMR
were recorded at 300 MHz (Bruker Avance 300 MHz). 13C
NMR spectra were recorded at 75 MHz. Tetramethylsilane
(TMS) was used as internal reference. Electron impact mass
spectra were performed on VG: 70 SE mass spectrometer.
(300 MHz, CDCl3): ꢀ 8.20-7.48 (m, 4H), 5.69 (s, 2H), 2.26
(s, 6H); 13C-NMR (75 MHz, CDCl3): ꢀ 170.1 (-COOR),
170.7 (-CON), 168.1 (-COOH), 135.3-126.0 (C6H4), 72.7 (-
CH-), 20.3 (CH3-CO); EIMS m/z (rel. abund. %): 335 (M+,
8), 295 (1), 232 (100), 194 (53), 163(38), 146 (79), 59 (36).
General Procedure for the Synthesis of Imides (3g-l) and
Amides (4a-f)
4-(3,4-Diacetoxy-2,5-dioxopyrrolidine-1-yl) Aniline (3j)
Yield: 79%, solid, M.p. = 117-118 ºC; IR (KBr): 2932
(C-H stretching), 1757 (CO imide), 1741 (CO ester), 1597
Imides and amides were synthesized by using 0.005 mole
(1.08 g) of diacetyl-L-tartaric acid anhydride (2,5-
dioxotetrahydrofuran-3,4-diyldiacetate), respective amine
(0.005 mole) and 10 mL of glacial acetic acid. The resulting
mixture was refluxed for one hour under nitrogen. Glacial
acetic acid was removed by extracting the reaction mixture
with ethyl acetate or chloroform and water. Products were
purified by column chromatography.
1
(aromatic) cm-1; H-NMR (300 MHz, CDCl3): ꢀ, 8.39-7.64
(m, 4H), 5.63 (s, 2H), 2.26 (s, 6H); 13C-NMR (75 MHz,
CDCl3): ꢀ 168.9 (-COOR), 170.1 (-CON), 147.4-136.1
(C6H4), 72.7 (-CH), 20.3 (CH3-CO); EIMS m/z (rel. abund.
%): 336 (M+, 35), 293 (4), 134 (22), 122 (11), 101 (100), 59
(8).
4-(3,4-Diacetoxy-2,5-dioxopyrrolidine-1-yl) Anisidine (3k)
3-(3,4-Diacetoxy-2,5-dioxopyrrolidine-1-yl)toluene (3g)
Yield: 76%, solid, M.p. = 150-152 ºC; IR (KBr): 2934
(C-H stretching), 1760 (CO imide), 1736 (CO ester), 1513
º
Yield: 68%, solid, M.p. = 106-108 C; IR (KBr): 2958
(C-H stretching), 1740 (CO imide), 1737 (CO ester), 1559
1
(aromatic) cm-1; H-NMR (300 MHz, CDCl3): ꢀ, 7.98-7.24
1
(aromatic) cm-1; H-NMR (300 MHz, CD3OD): ꢀ 7.41-7.13
(m, 4H), 5.66 (s, 2H), 2.24 (s, 6H), 3.84 (s,3H); 13C-NMR
(75 MHz, CDCl3): ꢀ, 168.7 (-COOR), 170.0 (-CON), 159.6-
114.6 (C6H4), 72.8 (-CH), 20.4 (CH3-CO), 55.5 (-OCH3);
EIMS m/z (rel. abund. %): 321 (M+, 23), 219 (100), 203 (2),
148 (80).
(m, 4H), 5.88 (s, 2H), 2.20 (s, 6H), 2.39 (s,3H); 13C-NMR
(75 MHz, CD3OD): ꢀ 169.3 (-COOR), 170.3 (-CON), 139.1-
123.3 (C6H4), 72.8 (-CH), 19.8 (CH3-CO), 19.4 (CH3-Ar);
EIMS m/z (rel. abund. %): 305 (M+, 5), 202 (100), 187 (2),
91 (16).
4-(3,4-Diacetoxy-2,5-dioxopyrrolidine-1-yl) Toludine (3l)
4-(3, 4-Diacetoxy-2,5-dioxopyrrolidine-1-yl)phenol (3h)
Yield: 73%, solid, M.p. = 118-120 ºC; IR (KBr): 2952
(C-H stretching), 1750 (CO imide), 1723 (CO ester), 1558
Yield: 75%, solid, M.p. = 73-75 ºC; FTIR (KBr): 3250-
2615(O-H), 2961 (C-H stretching), 1745 (CO imide), 1735
1
(aromatic) cm-1; H-NMR (300 MHz, Acetone d): ꢀ 7.35-
1
(CO ester) cm-1; H-NMR (300 MHz, CDCl3): ꢀ 7.68-7.38

Synthesis of Imides and Amides
Letters in Organic Chemistry, 2010, Vol. 7, No. 4
321
7.25 (m, 4H), 5.97 (s, 2H), 2.18 (s, 6H), 2.38 (s.3H); 13C-
NMR (75 MHz, CDCl3): ꢀ, 168.8 (-COOR), 170.0 (-CON),
138.7-126.5 (C6H4), 72.6 (-CH), 19.4 (CH3-CO); EIMS m/z
(rel. abund. %): 305 (M+, 5), 202 (100), 187 (2), 91 (16).
2.26 (s, 3H, -CH3), 2.24 (s, 3H, -CH3); 13C-NMR (75 MHz,
CDCl3): ꢀ, 170.0 (-CHCOOH), 168.2 (-COOR), 168.3 (-
COOR), 169.7 (-CON), 154.5-119.3 (C6H4), 72.4 (-CH),
73.0 (-CH-), 20.4 (-CH3), 20.4 (-CH3); EIMS m/z (rel. abund.
%): 339 (M+, 1), 308 (2), 222 (3), 204 (5), 108 (100).
2,3-Diacetoxy-4-(2-hydroxyphenyl amino)-4-oxobutanoic
Acid (4a)
4-(o-Toluidino)-2,3-diacetoxy-4-oxobutanoic Acid (4e)
º
Yield: 68%, liquid; FTIR (NaCl): 3503 (N-H stretching),
3559-2677 (O-H), 2941 (C-H stretching), 1750 (CO ester),
1730 (CO acid), 1670 (CO amide), 1599 (aromatic) cm-1; 1H-
NMR (300 MHz, CDCl3): ꢀ, 7.47 (dd, J = 7.8,1.5 Hz, 1H,
Ar), 6.98 (d,d, J =8.1,1.5 Hz, 1H, Ar), 6.93 (ddd, J = 7.6,
1.2, 1.2 Hz, 1H, Ar), 7.14 (d,d,d J = 8.4, 1.5, 1.5 Hz, 1H,
Ar), 5.97 (d, J = 2.4 Hz, 1H, -CH), 5.67 (d, J = 2.4 Hz, 1H, -
CH), 2.14 (s, 3H, -CH3), 2.27 (s, 3H, -CH3),8.30 (s,N-H),
7.37 (OH phenolic); 13C-NMR (75 MHz, CDCl3): ꢀ, 169.5 (-
COOH), 166.5(-COOR), 165.0 (-COOR), 168.5 (-CON),
147.5-118.3 (C6H4), 71.3(-CH-), 71.2 (-CH-), 20.3 (-CH3),
20.5 (-CH3).
Yield: 70%, solid, M.p. = 125-127 C; IR (KBr): 3510
(N-H stretching), 3448-2677 (O-H), 2948 (C-H stretching),
1735(CO ester), 1760 (CO acid), 1670 (CO amide), 1590
(aromatic) cm-1; H-NMR (300 MHz, CDCl3): ꢀ 7.40 (dd, J
1
= 7.8,1.5 Hz, 1H,Ar), 7.29 (d,d, J = 8.1,1.5 Hz, 1H, Ar),
7.21(ddd, J = 7.21, 1.2, 1.2 Hz, 1H, Ar), 7.35 (ddd, J =
8.4,1.5, 1.5 Hz, 1H, Ar), 5.74 (d, J = 5.1 Hz, 1H, -CH), 5.53
(d, J = 5.4 Hz, 1H, -CH), 2.24 (s, 3H, -CH3), 2.23 (s, 3H, -
CH3), 2.25 (Ar-CH3); 13C-NMR (75 MHz, CDCl3): ꢀ 170.2 (-
CHCOOH), 168.4 (-COOR), 168.5(-COOR), 170.1 (-CON),
147.5-118.3 (C6H4), 73.6 (-CH), 72.6 (-CH), 17.5 (-CH3),
17.6 (-CH3); EIMS m/z (rel. abund. %): 323 (M+, 6), 278 (2),
218 (71), 148 (100), 70(23).
2-(2,3-Diacetoxy-3-carboxypropanamido)benzoic Acid (4b)
3-(2,3-Diacetoxy-3-carboxypropanamido) Benzoic Acid (4f)
Yield: 75%, solid, M.p. = 103-105º C; IR (KBr): 3511
(N-H), 3250-2615 (O-H), 2903 (C-H stretching), 1750 (CO
Yield: 55%, liquid; IR (KBr): 3500 (N-H stretching),
3498-2600 (O-H), 2943 (C-H stretching), 1740 (CO
ester),1765 (CO acid), 1687 (CO amide), 1587 (aromatic)
1
ester), 1730 (CO acid), 1670 (CO amide) cm-1; H-NMR
(300 MHz, CD3OD): ꢀ 8.64 (dd, J = 7.0, 2.5 Hz, 1H, Ar),
8.13 (dd, J = 6.8, 3.0 Hz, 1H, Ar), 7.61 (ddd, J = 7.0, 2.0, 2.0
Hz, 1H, Ar), 7.21 (ddd, J = 7.2, 3.1, 3.1 Hz, 1H, Ar), 5.87 (d,
J = 2.1 Hz, 1H,-CH), 5.70 (d, J = 2.4 Hz, 1H, -CH), 2.30 (s,
3H, -CH3), 2.05 (s, 3H, -CH3); 13C-NMR (75 MHz, CD3OD):
ꢀ 170.0 (-CHCOOH), 169.4 (-COOR), 168.4 (-COOR),
169.8 (-CON), 165.4 (Ar-COOH), 140.0-116.1 (C6H4), 72.4
(-CH), 71.2 (-CH-), 19.1 (-CH3), 18.8 (-CH3); Anal. Calcd.
for C15H15O9N: C, 50.99; H, 4.27; N, 3.96. Found: C, 49.67;
H, 4.57; N, 3.88.
1
cm-1; H-NMR (300 MHz, CD3OD): ꢀ 8.18 (dd, J = 1.8,1.8
Hz, 1H, Ar), 7.81-7.78 (m, 2H, Ar), 7.43 (dd, J = 8.1, 7.8
Hz, 1H, Ar), 5.71 (d, J = 2.7 Hz, 1H, -CH), 5.55 (d, J = 2.7
Hz, 1H, -CH), 2.21 (s, 3H, -CH3), 2.11 (s, 3H, -CH3); 13C-
NMR (75 MHz, CD3OD): ꢀ 170.0 (-CHCOOH), 167.0 (-
COOR), 170.5 (-ArCOOH), 167.0 (-COOR), 168.6 (-CON),
137.7-121.8 (C6H4), 73.1 (-CH-), 74.0 (-CH), 19.3 (-CH3),
19.2 (-CH3); Anal. Calcd. for C15H15O9N: C, 50.99; H, 4.27;
N, 3.96. Found: C, 49.67; H, 4.57; N, 3.88.
2,3-Diacetoxy-4-(2-nitrophenylamino)-4-oxobutanoic Acid
(4c)
ACKNOWLEDGEMENT
Yield: 71%, solid, M.p. = 110-111 ºC; IR (KBr): 3503
(N-H stretching), 3250-2615 (O-H), 2941 (C-H stretching),
1753(CO ester), 1725 (CO acid), 1690 (CO amide),
1587&1346 (N-O stretching) cm-1; 1H-NMR (300 MHz,
Acetone d6): ꢀ 8.57 (dd, J = 6.8,3.0 Hz, 1H,Ar), 8.26 (d,d, J
= 6.5,3.0 Hz, 1H, Ar), 7.852 (ddd, J = 7.1, 3.2, 3.2 Hz, 1H,
Ar), 7.41 (ddd, J = 7.0, 2.0, 2.0 Hz, 1H, Ar), 5.93 (d, J = 3.0
Hz, 1H, -CH), 5.69 (d, J = 3.0 Hz, 1H, -CH), 2.25 (s, 3H, -
CH3), 2.08 (s, 3H, -CH3); 13C-NMR (75 MHz, Acetone d6): ꢀ
169.2 (-CHCOOH), 167.7 (-COOR), 167.4 (-COOR), 168.7
(-CON), 138.1-122.4 (C6H4), 72.4 (-CH-), 71.0 (-CH), 19.6
(-CH3), 19.4 (-CH3); Anal. Calcd. for C14H14O9N2: C, 47.46;
H, 3.98; N, 7.90. Found: C, 46.65; H, 4.13; N, 7.77; EIMS
m/z (rel. abund. %): 354 (M+, 4), 217 (8), 189 (3), 137 (100),
91 (26), 65 (25).
This work was financially supported by the Higher
Education Commission (HEC) Pakistan under “National
Research Program for Universities.”
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