Synthetic Communications®, 35: 913-922, 2005
Copyright © Taylor & Francis, Inc.
ISSN 0039-7911 print/1532-2432 online
DOI: 10.I081/SCC-200051681(^"^ Taylor & Francis^

Fe-HCl: An Efficient Reagent for
Deprotection of Oximes as well as Selective
Oxidative Hydrolysis of Nitroalkenes andNitroalkanes to Ketones
Prasun K. Pradhan, Sumit Dey, Parasuraman Jaisankar, andVenkatachalam S. Giri
Department of Medicinal Chemistry, Indian Institute of Chemical
Biology, Calcutta, India

Abstract: Fe-HCl mixture was found to selectively perform oxidative hydrolysis of thenitroalkenes l a - j and nitroalkanes 2a-j to the ketones 3a-j. Also, the reagent wasobserved to deprotect the oximes 7a-j to carbonyl compounds 8a-j in excellent yields.
Keywords: Deprotection of oximes, Fe, HCI, hydrolysis, ketones, nitroalkanes,
nitroalkenes, oxidation

INTRODUCTION
Nitro compounds are important intermediates in synthetic organic chemistrybecause they can be converted easily into other desired functional groups. The
formation of ketones and aldebydes by oxidative hydrolysis from the corresponding nitroalkanes is one of the important transformations that has tremendous
synthetic utility. Nef reaction^" involves oxidative hydrolysis of the nitronate
salts of primary or secondary nitroalkanes to aldehydes or ketones understrong acidic conditions. Komblum et al. have used potassium permanganate
Received Novemher 11, 2004
Address correspondence to Venkatachalam S. Giri, Department of Medicinal
Chemistry, Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road,
Calcutta 700 032, India. Tel.: -f 91-33-24733491; Fax: +91-33-24735197; E-mail:vsgiri@iicb.res.in

914

P. K. Pradhan et al.

for converting nitroparaffin salts to ketones and aldehydes in good yield.'^^ It isalso known that ozonolysis of the nitroalkenes results in the formation of the
carbonyl compounds. Later it was observed by McMurry et al. that nitroalkanes
upon treatment with Ti(in)chloride followed by hydrolysis, afford the aldehydes
in good yield. In a recent review,'^"'' Ballini et al. have given an up-to-dateaccount of Nef reaction and its applications.
RESULTS AND DISCUSSION
In the course of preparation of some aryl ethylamine derivatives, we observedthat Fe-HCI could bdng about the oxidative hydrolysis of both secondary
nitroalkenes l a - j and nitroalkanes 2a-j to the ketones 3a-j in very goodyield (Scheme 1). Usually a mixture of iron and aqueous hydrochloric acid isused for reduction of nitro groups to amino groups. This is the first report ofsuch an oxidative hydrolysis of both nitroalkanes and nitroalkenes to the
ketones using Fe and hydrochloric acid. The results are summarized in Table 1.
Interestingly, the reagent selectively converts the nitroalkenes l a - j andnitroalkanes 2a-j that have a methyl group a- to the NO2 functionality to
the ketones 3 a - j , whereas those having an a-hydrogen 4 a - d and 5a-d are
reduced to the corresponding amines 6a-d (Scheme 2), and the yields are
summarized in Table 2.
The nitroalkenes l a - j or 4 a - d obtained from the condensation bystandard procedures of the aldehydes and nitroethane or nitromethane,respectively, are reduced to the corresponding nitroalkanes 2 a - j or 5a-dby using NaBH4-Dioxane-ethanol.'^'Oximes are important derivatives used for both purification and isolationof carbonyl compounds. Carbonyl compounds are easily converted into
oximes by refluxing with hydroxylamine hydrochloride in ethanol. The
oximes are potential intermediates in organic synthesis.^'^^ Oximes not only
serve as protecting groups for carbonyl compounds''*''^ but also have otheruses such as preparation of nitriles, preparation of amides via Beckmann
rearrangement, or to activate the carbonyl groups. However, the methods so
far developed to regenerate carbonyl compounds from oximes consist ofoxidative or reductive reaction. Most of the methods involve reagents thatare often hazardous or very toxic, expensive, or not readily available.
Although deprotection of oximes is well known, our method is a very

Fe-HCINO2 MeOH-HaO

0
3
Scheme 1.

MeOH-H2O

YNO22An Efficient Reagent for Deprotection and Selective Oxidative Hydrolysis

915

Table 1. Conversion of nitroalkenes l a - j and nitroalkanes 2a-j to ketones 3a-j
Percent of yield(isolated)
Entry

Substrates 1 or 2 R =abphenyl
4-methoxyphenylc4-hydroxy-3methoxyphenyld3,4,5 - trimethoxy phenyle4-hydroxyphenylf3-inciolylg

1 -benzo-( 1,3)dioxole-5-ylh4-nitrophenyli

2- furylj3-nitro-4-(methoxycarbonylmethoxy)phenyl

Products 3

From 1

From 2

1 -phenyl-propan-2-one
1 -(4-methoxy-phenyl)propan-2-one
1 -(4-hydroxy-3-methoxy-phenyl) propan2-one
1 -(3,4,5-triniethoxy-phenyl)propan-2-one
1 -(4-hydroxy-phenyl)propan-2-onel-(lH-indol-3-yl)propan-2-one
1 -benzo-( 1,3)-dioxole-5yl propan-2-one
1 -(4-aniino-phenyl)propan-2-one
1 -(furan-2-yl) propan-2one
6-(2-oxo-propyl)-4Hbenzo-( 1,4)-oxazin-3one

82
80

85
82

90

95

80

85

81

84

78

85

85

89

83

80

75

81

92

95

simple, efficient, and facile method for deprotection of oximes (Scheme 3).
The yields of carbonyl compounds 8 a - j from their oximes 7 a - j aresummarized in Table 3. The reaction takes place only when a mixture of Fe
and HCl is used but does not occur in the absence of one of them (Fe or HCl).
It is well known that reduction of nitro groups to the amines takes placethrough the intermediacy of the nitroso derivatives of the oximes. We believethat in the cases of nitroalkenes l a - j and nitroalkanes 2a-j, because of
the presence of a methyl group a to the NO2 functionality, oximes
are generated that subsequently undergo oxidative hydrolysis to the ketones
3 a - j . On the other hand, nitroalkenes 4a-d and nitroalkanes 5a-d are

R

Fe-HCl^Fe-HCl

R
NH2
6

Scheme 2.

F

MeOH-HjO

NO2
5

916
Table 2.

P. K. Pradhan et al.
Conversion of nitroalkenes 4a-d and nitroalkanes 5a-d to the amines 6a-d
Percent yield of 6 (isolated)
Substrate 4 or 5

From 4

From 5

3,4,5- trimethoxyphenyl
benzo-( 1,3)-ciioxole-5-yl
phenyl3-indolyl

72
70
63
71

75
71
65
76

Entry
a
b
c
d

converted to the nitroso group, which spontaneously undergoes reduction to thecorresponding amines 6a-d through the intermediacy of the hydroxylamines.
In conclusion, the Fe and aq. HCl system is an efficient reagent for
deprotection of oximes and also for selective conversion of both nitroalkenes
and nitroalkanes to the same ketones.

EXPERIMENTAL
All melting points were determined in open capillaries on SPAC-N-SERVICE(India) capillary melting point apparatus and are uncorrected. IR spectra wererecorded on a JASCO-FT-IR Model 410 using samples as KBr plates.
' H N M R (300 MHZ) and '^C NMR (75 MHz) were recorded on a Bruker
DPX 300 NMR instrument using TMS as internal standard. Elemental
analyses were done on a PERKIN ELMER 2400 Series II CHNS/0
analyzer. Mass spectra ESI and EI were recorded on Q-TOF Micro mass
(LCMS) spectrometer and JEOL-AX-500 spectrometer respectively.

Typical Experimental Procedure for Conversion of Nitro Alkanes
or Nitro Alkenes or Oximes to Carbonyl Compounds
To a solution of nitroalkane or nitroalkene or oxime (3 mmol) in a mixtureof MeOH (5mL), HjO (2mL), and cone. HCl (2mL), iron dust (336 mg;
6 mmol) was added in portions and the resulting reaction mixture was

Fe-HClR>MeOH-HzO

^2

• > 8

Scheme 3.

An Efficient Reagent for Deprotection and Selective Oxidative Hydrolysis
Tabte 3.

Conversion of oximes 7a-j to the corresponding carbonyl compounds 8a-j

Entry

a
b
c
d

e
f
g

h
i
j

917

Percentyield of 8

Oximes 7

Carbonyl compounds 8

Benzaldehyde oxime
Benzo( 1,3)dioxole-5-carbaldehyde oxime
Chroman-4-one-oxime
6-(2-Hydroxyamino-propyl)-4H-benzo(l ,4)oxazine-3-one
Furan-2-carbaldehyde oxime
4-Nitro-benzaldehyde oxime
1 -(4-Hydroxy-3-methoxyphenyl)-propan-2-one
oxime
1-Phenyl-ethanone oxime
Diphenyl-methanone oxime
4-Methoxy benzaldehyde
oxime

Benzaldehyde
Benzo( 1,3)dioxole-5carbaldehyde
Chroman-4-one
6-(2-Oxo-propyl)-4H-benzo( 1,4)oxazine-3-one

94
85

Furan-2-aldehyde
4-amino-benzaldehyde
1 -(4-Hydroxy-3-methoxyphenyl)-propan-2-one

81
90
82

1 -Phenyl-ethanone
Diphenyl-methanone
4-Methoxy benzaldehyde

84
81
90

80
82

refluxed over a steam bath for 30 min. After complete disappearance ofthe starting material (monitored by TLC using 1% MeOH in CHCI3), thereaction mixture was filtered over a bed of celite using MeOH. The
filtrate was concentrated and diluted with H2O (10 mL) either basified in
the case of amitie products or directly extracted with CHCI3 (3 x 10 mL).
The CHCI3 layer was then dried (Na2SO4), the solvent was removed under
reduced pressure, and the residue was chromatographed over silica gelusing increasing concentrations of CHCI3 in petroleum ether or direct crystallization to the desired ketone in pure form. The compounds have been characterized mainly from their physical data, particularly NMR, and confirmed bycomparison with authentic specimens obtained by standard procedures.
The following compounds are already known in the literature: la,'^^ lb,'^^
'^l
[251

t«'

t^]
[26]

f51

['O]

['"

l'^l

f^

[28]

l,2,3-Trimethoxy-5-(2-nitro-propenyl)benzene (Id). Mp 66-68°C;
IR (KBr): u = 2940, 2223, 1582, 943, 851cm"'; ' H NMR (CDCI3):
5 = 2.49 (s, 3H), 3.90 (s, 9H), 6.66 (s, 2H), 6.86 (s, IH); MS (ESI): 254(M-|-H)+. Anal, calcd. for C^HisNOs: C, 56.91; H, 5.97; N, 5.53. Found:C, 56.79; H, 6.01; N, 5.60.
3-(2-Nitro-propenyl)-lH-indole (If), Mp 186-188 °C; IR (KBr):
v = 3425, 1627, 1525, 1478, 1269, 1222, 1126, 971, 857, 750cm"'; ' H
NMR (CDCI3): S = 2.54 (s, 3H), 7.27-7.36 (m, 2H), 7.46 (d, 7 = 6.8 Hz,

918

P. K. Pradhan et al.

IH), 7.57 (s, IH), 7.83 (d, 7 = 7.2Hz, IH), 8.52 (s, IH), 8.74 (brs, NH); MS(ESI): 203 (M + H)+. Anal, calcd. for C11H10N2O2: C, 65.34; H, 4.98; N,
13.85. Found; C, 65.50; H, 5.02; N, 13.91.
[2-Nitro-4-(2-nitro-propenyl)-phenoxy]aceticacidmethylester(lj). Liquid; IR (neat); v = 3429, 1641 cm"'; ' H NMR (CDCI3); 8 = 2.46(s, 3H), 3.83 (s, 3H), 4.86 (s, 2H), 7.06 (d, 7 = 8 . 7 Hz, IH), 7.59
(d, 7 = 8 . 7 H z , IH), 7.98 (s, IH), 8.0 (d, 7 = 5 . 1 Hz, IH); MS (ESI);
297(M + H)+. Anal, calcd. for C12H12N2O7; C, 54.90; H, 4.6t; N, 9.15.
Eound; C, 55.01; H, 4.67; N, 9.21.
l-Methoxy-4-(2-nitro-propyl)benzene (2b). Liquid; IR (neat);u = 2937, 1610, 1549, 757 cm"';'HNMR(CDCI3): S = 1 . 5 2(d, 7 =6.9Hz, 3H), 2.95 (dd, 7 =6.66Hz, 14.0Hz, IH), 3.24 (dd,
7 = 6.65Hz, 14.0Hz, IH), 3.77 (s, 3H), 4.72 (sext, 7 = 6.76Hz, IH), 6.83
(d, 7 = 8.56 Hz, 2H), 7.07 (d, 7 = 8.22 Hz, 2H); MS (ESI): 196 (M + H)+.
Anal, calcd. for C10H13NO3: C, 61.53; H, 6.71; N, 7.18. Found; C, 61.42;
H, 6.78; N, 7.27.
2-Methoxy-4-(2-nitro-propyl)phenot(2c). Liquid;IR(neat):
i, = 3471, 1548, 1032, 797cm"'; ' H NMR (CDCI3): 5 = 1 . 5 3(d, 7 =6.64Hz, 3H), 2.94 (dd, 7=6.66Hz, 14.01 Hz, IH), 3.24 (dd,
7 = 7.50Hz, 14.01 Hz, IH), 3.86 (s, 3H), 4.73 (sext, 7 = 6.70Hz, IH), 5.61
(brs, OH), 6.56 (s, IH), 6.65 (d, 7 = 9.9Hz, IH), 6.95 (d, 7 = 8.2Hz, IH);
MS (ESI): 212 (M + H)+. Anal, calcd. for C,oH|3N04: C, 56.86; H, 6.20;
N, 6.63. Found; C, 56.68; H, 6.28; N, 6.71.
l,2,3-Trimethoxy-5-(2-nitro-propyl)benzene (2d). Liquid; IR (neat):11 = 3430, 1549, 922cm"'; ' H NMR (CDCI3): 5 = 1 . 5 6 (d, 7 = 6 . 6 H z ,3H), 2.94 (dd, 7 = 6.6Hz, 14.0Hz, IH), 3.28 (dd, 7 = 6.6Hz, 14.0Hz, IH),
3.82 (s, 9H), 4.73 (sext, 7 =6.64Hz, IH), 6.36 (s, 2H); MS (ESI): 256(M + H)+. Anal, calcd. for C^HnNOs: C, 56.46; H, 6.71; N, 5.49. Found:C, 56.34; H, 6.80; N, 5.57.
4-(2-Nitropropyt)pbenot (2e). Liquid; IR (neat): v = 3390, 1546,
770cm"'; ' H NMR (CDCI3): 8 1.53 (d, 7 = 6 . 9 H z , 3H), 2.94 (dd,
7 =6.5Hz, 14.0Hz, IH), 3. 23 (dd, 7 =6.6Hz, 14.0Hz, IH), 4.73 (sext,
7 = 6 . 5 Hz, IH), 5.29 (brs, OH), 6.78 (d, 7 = 6 . 9 Hz, 2H), 7.04
(d, 7 = 6.9Hz, 2H); MS (ESI): 182 (M + H)+. Anal, calcd. for C9H,iNO3:
C, 59.66; H, 6.12; N, 7.73. Found: C, 59.54; H, 6.89; N, 7.81.
3-(2-Nitro-propyt)-lH-indole (2f). Liquid; IR (neat): v = 3417, 1546,
745 cm"'; ' H NMR (CDCI3): 8= 1.523 (d, 7 = 6 . 2 H z , 3H), 3.16 (dd,
7 = 6 . 2 H z , 14.5HZ, IH), 3.44 (dd 7 = 7 . 2 H z , 14.5 Hz, IH), 4.85 (sext,
7 = 6.3Hz, IH), 6.91 (s, IH), 7.08-7.17 (m, 2H), 7.30 (d, 7 = 7.6Hz, IH),
7.54 (d, 7 = 7.6Hz, IH), 8.03 (brs, NH); MS (ESI); 205 (M + H)+. Anal,
calcd. for C,,H,2N2O2: C, 64.69; H, 5.92; N, 13.72. Found: C, 64.54; H,
5.99; N, 13.83.
5-(2-Nitro-propyl)benzo(l,3)dioxole(2g). Liquid;IR(neat):
u = 2900, 1550, 930cm"'; ' H NMR (CDCI3): 5 = 1 . 5 3 (d, 7 = 6 . 6 H z ,An Efficient Reagent for Deprotection and Selective Oxidative Hydrolysis

919

3H), 2.92 (dd, y = 6.6HZ, 14.0 Hz, lH), 3.22 (dd, 7 = 7.6 Hz, 14.0 Hz, lH),
4.71 (sext, y = 6.8Hz, lH), 5.93 (s, 2H), 6.61 (d, 7 = 7.8Hz, lH), 6.63(s, lH), 6.74 (d, J = 7.8Hz, lH); MS (ESI): 210 (M + H)+. Anal, calcd. for
C|oHnN04: C, 57.41; H, 5.30; N, 6.70. Found: C, 57.30; H, 5.39; N, 6.78.
2-(2-Nitro-propyl)furan (2i). Liquid; IR (neat): u = 3420, 1537,
756cm"'; ' H NMR (CDCI3): S = 1 . 5 7 (d, y = 6.7Hz, 3H), 2.37 (dd,y = 7 . 2 H z , 15.2HZ, lH), 3.80 (dd, y = 6 . 7 H z , 15.2Hz, lH), 4.84 (sext,
7 = 6 . 8 Hz, lH), 6.13 (d, 7 =2.53 Hz, lH), 6.30 (d, 7 = 2 . 8 Hz, lH), 7.33
(s, lH); MS (ESI): 156 (M + H)+. Anal, calcd. for C7H9NO3; C, 54.19; H,
5.85; N, 9.03. Found: C, 54.05; H, 5.92; N, 9.10.
(2-Nitro-4-(2-nitro-propyl)phenoxy(acetic
acid
methylester(2j). Liquid; IR (neat): u = 3439, 1743, 1626, 814, 755cm~'; ' H NMR(CDCI3): 5 = 1.59 (d, 7 = 6.7 Hz, 3H), 3.04 (dd, 7 = 5.8 Hz, 14.4 Hz, lH),
3.30 (dd, 7 = 8.3Hz, 14.4Hz, lH), 3.80 (s, 3H), 4.74 (s, 2H), 4.75-4.80(m, lH), 6.94 (d, 7 = 8.6Hz, lH), 7.30 (d, 7 = 8.6Hz, lH), 7.71 (s, lH);
MS (ESI): 299 (M + H)+. Anal, calcd. for C12H14N2O7: C, 48.32; H, 4.73;
N, 9.39. Found: C, 48.21; H, 4.80; N, 9.46.
l-(3,4,5-Trimethoxy-phenyl)propan-2-one (3d). Liquid; IR (neat):11 = 3513, 1710, 1590, 917cm~'; ' H NMR (CDCI3): 5 = 2.18 (s, 3H), 3.63(s, 2H), 3.84 (s, 9H), 6.41 (s, 2H); MS (ESI): 225 (M + H)+: Anal, calcd.
for C,2H|6O4: C, 64.27; H, 7.19. Found: C, 64.41; H, 7.26.
l-(4-Hydroxy-phenyl)propan-2-one(3e). Liquid;IR(neat):
u = 3357, 1698, 1513, 757cm"'; ' H NMR (CDCI3): 6 = 2.16 (s, 3H), 3.63(s, 2H), 6.40 (brs, OH), 6.80 (d, 7 =8.30 Hz, 2H), 7.02 (d, 7 =8.30 Hz,2H); MS (ESI): 151 (M + H)+. Anal, calcd. for C9H10O2: C, 71.98; H,
6.7L Found: C, 71.86; H, 6.77.
l-(lH-Indol-3-yl)propan-2-one (3f). Mp 104-106°C. IR (KBr):
u = 3327, 1708, 752cm~'; ' H NMR (CDCI3): S = 2.15 (s, 3H), 3.8(s, 2H), 7.07 (s, lH), 7.10-7.23 (m, 2H), 7.34 (d, 7 = 7.71 Hz, lH), 7.52
(d, 7 = 7.71 Hz, lH), 8.2 (brs, NH); MS (ESI): 174 (M + H)+. Anal, calcd.
forCiiHiiNO: C, 76.28; H, 6.40; N, 8.09. Found: C, 76.13; H, 6.46; N, 8.15.
l-(4-Amino-phenyl)propan-2-one (3h). Liquid; IR (neat): v = 3363,
1703, 1624, 1515cm"'; ' H NMR (CDCI3): 5 = 2.14 (s, 3H), 3.57 (s, 2H),
4.17 (brs, NH2), 6.49 (d, 7 = 8.41 Hz, 2H), 7.14 (d, 7 = 7.95 Hz, 2H); MS(ESI): 150 (M + H)+. Anal, calcd. for CgHnNO: C, 72.46; H, 7.43; N,
9.39. Found: C, 72.33; H, 7.50; N, 9.48.
l-Furan-2-yl-propan-2-one(3i). Liquid; IR (neat): v = 3282, 2923,
1712, 743 cm"'; ' H NMR (CDCI3): S = 1.88 (s, 3H), 3.52 (s, 2H), 6.12
(d, 7 =2.22 Hz, lH), 6.20 (d, 7 =2.90 Hz, lH), 7.33 (s, lH); MS (ESI):
125 (M + H)+. Anal, calcd. for C7H8O2: C, 67.73; H, 6.50. Found: C,
67.99; H, 6.58.
6-(2-Oxo-propyl)-4H-benzo(l,4(oxazine-3-one (3j). Mp 154-156°C;
IR (KBr): i; = 3197, 1710, 1688, 800cm"'; ' H NMR (CDCI3): 5 = 2.18
(s, 3H), 3.64 (s, 2H), 4.61 (s, 2H), 6.67 (s, lH), 6.79 (d, 7 = 8.16Hz, lH),

920

P. K. Pradhan et al.

6.93 (d, 7 = 8.16Hz, IH), 8.86 (hrs, NH); '^C NMR (CDCI3): (S = 29.82,
50.25, 67.51, 117.28, 117.50, 125.56, 126.75, 129.08, 143.12, 166.80, and206.79; MS (ESI): 206 (M-fH)+. Anal, calcd. forC,|HnNO3: C, 64.38; H,
5.40; N, 6.83. Found: C, 64.50; H, 5.59; N, 6.90.
2-(3,4,5-Trimethoxy-phenyl)ethylamine (6a). Liquid; IR (neat):V = 3412, 1645, 996, 826cm"'; ' H NMR (CDCI3): 5 = 2.73 (t, 7 = 6.78Hz,
2H), 2.98 (t, J = 6.74 Hz, 2H), 2.91 (brs, 2 x NH), 3.84 (s, 9 H), 6.43 (s, 2H);'^C NMR (CDCI3): (5 = 39.02, 46.12, 61.27 (2 x C), 65.78, 111.01 (2 x C),
137.95, 141.82, 158.42 (2 x C); MS: 212 (M-l-H)+. Anal, calcd. for
Ci,H|7NO3: C, 62.54; H, 8.11; N, 6.63. Found: C, 62.42; H, 8.15: N, 6.69.
2-Benzo(l,3(dioxole-5-yl-etbylaniine(6b). Liquid;
IR (neat):u = 3412, 1653, 809cm"'; ' H NMR (CDCI3): 8 1.74 (hrs, NH2), 2.66
(t, 7 =6.69 Hz, 2H), 2.91 (t, 7 =6.57 Hz, 2H), 5.91 (s, 2H), 6.50-6.80(m, 3H); MS (ESI): 166 (M + H)+. Anal, calcd. for C9HnNO2: C, 65.44;
H, 6.71; N, 8.48. Found: C, 65.31; H, 6.78, N, 8.54.
6-(2-Hydroxyimino-propyl)-4H-benzo-(l,4)oxazine-3-one (7d). Mp
143-144°C; IR (KBr): i; = 3216, 1688, 806cm~'; ' H NMR (CDCI3):
5 = 1.65 (s, 3H), 3.16 (s, 2H), 3.18 (s, 2H), 6.70-7.06 (m, 3, H), 10.49(hrs, IH), 10.66 (s, IH); '^C NMR (DMSO-dg): (S = 13.78, 41.48, 67.59,
116.76, 116.89, 124.25, 128.11, 132.57, 142.77, 155.28, 165.83; MS (ESI):
221 (M-|-H)+. Anal, calcd. for C11H12N2O3: C, 59.99; H, 5.49; N, 12.72.
Found: C, 59.83; H, 5.54; N, 12.78.
l-(4-Hydroxy-3-metboxy-pbenyl)propan-2-one oxime (7g). Liquid;
IR (neat): u = 3370, 1661, 1514, 793cm"'; ' H NMR (CDCI3): 5 = 1.79
(s, 3H), 3.41 (s, 2H), 3.79 (s, 3H), 3.85 (s, lH), 6.66-6.90 (m, 4H); MS(ESI): 196 (M + H)+. Anal, calcd. for C,oH|3N03: C, 61.53; H, 6.71; N,
7.18. Found: C, 61.42; H, 6.79; N, 7.24.

ACKNOWLEDGMENT
S. D. thanks University Grants Commission, New Delhi, India, for JuniorResearch Fellowship and the other authors thank Council of Scientific andIndustrial Research, New Delhi, India, for the generous grant.

REFERENCES
1. (a) Nef, J. K. Formation of aldehydes and ketones from primary and secondary
nitroalkanes, respectively, by treatment of their salts with sulfuric acid. Ann.
Chem. 1894, 280, 263; (b) Ballini, R.; Petrini, M. Recent synthetic developmentsin the nitro to carbonyl conversion Nef reaction. Tetrahedron 2004, 60,
1017-1047and references cited therein.
2. Komblum, N.; Erickson, A. S.; Kelly, W. J.; Henggeler, B. Conversion of nitro
paraffins into aldehydes and ketones. 7. Org. Chem. 1982, 47, 4534-4538.

An Efficient Reagent for Deprotection and Selective Oxidative Hydrolysis

921

3. Bhattacharjya, A.; Mukhopadhyay, R.; Pakrashi, S. C. Sodium borohydride
reduction of nitrostyrenes by reverse addition: a simple and efficient method forthe large-scale preparation of phenylnitroethanes. Synthesis 1985, 886-887.
4. (a) Preparation and the Synthetic Utility of Oximes; Sandier, S. R.; Karo, W.
Organic Functional Group Preparations, 2nd Ed.; Academic Press: San Diego,
1989; 431-476; (b) Green, T. G.; Wuts, P. G.M. Protective Groups in Organic
Synthesis, 2nd Ed.; John Wiley & Sons: Toronto, 1999; Vol. 3 pp. 172-223.
5. Mourad, M. S.; Verma, R. S.; Kabalka, G. W. Reduction of alpha, beta-unsaturated
nitro compounds with boron hydrides: a new route to N-substituted hydroxylamines. J. Org. Chem. 1985, 50, 133-135.
6. Karmarkar, S. N.; Kelkar, S. L.; Wadia, M. S. A simple unusual one step conversion of aromatic aldehydes into nitriles. Synthesis 1985, 510-512.
7. Pearl, I. A.; Beyer, D. L. Reactions of vanillin and its derived compounds, XII:
benzyl methyl ketones derived from vanillin and its related compounds. J. Org.
Chem. 1951,76,221-224.
8. Gairaud, C. B.; Lappin, G. R. The synthesis of o>-nitrostyrenes. J. Org. Chem.
1953, 18, 1-3.
9. Schales, O.; Graefe, H. A. Arylnitroalkenes: a new group of antibacterial agents.
J. Am. Chem. Soc. 1952, 74, 4486-4490.
10. Rosini, G.; Ballini, R.; Petrini, M.; Sorrenti, P. A convenient synthesis of l-(2furyl)-2-nitroalk-1-enes on alumina surface without solvent. Synthesis 1985,
515-517.
11. Bachman, G. B.; Maleski, R. J. Nitration studies. XVIII. conversion of lower
nitroalkanes to higher members of the series. J. Org. Chem. 1972,37,2810-2814.
12. Huber, D.; Andermann, G.; Leclerc, G. Selective reduction of aromatic/aliphatic
nitro groups by sodium sulfide. Tetrahedron Lett. 1988, 29, 635-638.
13. Chou, T. S.; Hung, S. B. Non-Wittig type reaction of Tebbe reagent with acyl
chloride. Tetrahedron Lett. 1983, 24, 2169-2170.
14. Kosugi, M.; Suzuki, M.; Hagiwara, I.; Goto, K.; Saitoh, K.; Migita, T. A new
palladium catalyzed aromatic acetonylation by acetonyltributyltin. Chem. Lett.
1982, 939-940.
15. Elks, J.; Hey, D. H. /3-3,4-Methylenedioxyphenyl isopropyl amine. J. Chem. Soc.
1943, 15-16.
16. Dauzonne, D.; Royer, R. A versatile synthesis of l-aryl-2-nitro-3-(3,4,5-trimethoxyphenyO-propenes as precursors of novel mescaline derivatives. Chem.
Pharma. Bull 1986, 34, 1628-1633.
17. Barton, D. H.R.; Bhakuni, D. S.; Chapman, G. M.; Kirby, G. W. Phenol oxidation
and biosynthesis. Part XV: the biosynthesis of roemerine, anonaine and mecambrine. J. Chem. Soc. C 1967, 2134-2140.
18. Worrall, D. E.; Marvel, C. S.; Lycan, W. H. P-Nitrostyrene Organic Syntheses,
Coll.; Vol. 1; 2nd ed. John Wiley & Sons; New York, 1956; pp. 413-415.
19. Buchi, G.; Mark, C.-P. Nitro olefination of indoles and some substituted benzenes
with l-dimethylamino-2-nitroethylene. / Org. Chem. 1977, 42, 1784-1786.
20. Ranganathan, D.; Rao, C. B.; Ranganathan, S.; Mehrotra, A. K.; Iyengar, R.
Nitroethylene: a stable, clean, and reactive agent for organic synthesis. / Org.
Chem. 1980,45, 1185-1189.
21. Robinson, J. C, Jr.; Snyder, H. R. /3-Phenylethyl amine. Org. Synth. 1943, 23,
71-74.
22. Jackson, A. H.; Smith, A. E. The melting point and structure of tryptamine.
J. Chem. Soc. 1965, 3498-3500.

922

P. K. Pradhan et al.

23. Auwers, K. V.; Ottens, B. Configuration of stereoisomeric oximes and the structureof oxime N-ethers and aci-nitro derivatives. Chem. Ber. 1924, 57B, 446-61.
24. Knudsen, R. D.; Morrice, A. G.; Snyder, H. R. p-Cyanophenol from p-nitrobenzaidoxime by an apparent dehydration-displacement, and a suggested modification of
the Miiler-Loudon conversion of aldehydes to nitriles. J. Org. Chem. 1975, 40,
2878-2880.
25. Powell, S. G. Beta-phenoxypropionic acid and some of its derivatives. Chromanone. J. Am. Chem. Soc. 1923, 45, 2708-2711.
26. Forster, M. O.; Dunn, F. P. Interpretation of the Hantzsch-Wemer hypothesis.
J. Chem. Soc. 1909, 95, 425-433.
27. Bouveault, J. Bull. Soc. Chim. 1897, 17, 1020.
28. Lachman, A. Benzophenone oxime. Org. Synth. 1930, 10, 10-11.
29. Blackwell, M.; Dunn, P. J.; Graham, A. B.; Grigg, R.; Higginson, P.; Saba, 1. S.;
Pett, T. M. X = Y - ZH systems as potential 1,3-dipoles, Part 56: Cascade 1,3azaprotio cyclotransfer-cycloaddition reactions between aldoximes and divinyl
ketone: the effect of oxime E/Z isomerism on cycloaddition stereoselectivity.
Tetrahedron 2002, 58, 7715-7725.