Synthesis of new and novel N-protected 1-aminoalkyl-2-naphthol derivatives

Article abstract of DOI:10.1080/00397910802659194

A series of three-component reactions has been carried out using HClO4-SiO2 as a versatile heterogeneous catalyst. A series of new and novel N-protected 1-aminoalkyl-2-naphthol derivatives have been prepared under thermal solvent-free reaction conditions.

Full text of DOI:10.1080/00397910802659194

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Synthesis of New and Novel
N-Protected 1-Aminoalkyl-2-
naphthol Derivatives
Hamid Reza Shaterian a , Asghar Hosseinian a &
Majid Ghashang a
a Department of Chemistry , Faculty of Sciences,
University of Sistan and Baluchestan , Zahedan, Iran
Published online: 16 Jun 2009.
To cite this article: Hamid Reza Shaterian , Asghar Hosseinian & Majid Ghashang
(2009) Synthesis of New and Novel N-Protected 1-Aminoalkyl-2-naphthol Derivatives,
Synthetic Communications: An International Journal for Rapid Communication of
Synthetic Organic Chemistry, 39:14, 2560-2574, DOI: 10.1080/00397910802659194
To link to this article: http://dx.doi.org/10.1080/00397910802659194
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Synthetic Communications1, 39: 2560–2574, 2009
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397910802659194
Synthesis of New and Novel N-Protected
1-Aminoalkyl-2-naphthol Derivatives
Hamid Reza Shaterian, Asghar Hosseinian, and Majid Ghashang
Department of Chemistry, Faculty of Sciences, University of Sistan and
Baluchestan, Zahedan, Iran
Abstract: A series of three-component reactions has been carried out using
HClO4-SiO2 as a versatile heterogeneous catalyst. A series of new and novel
N-protected 1-aminoalkyl-2-naphthol derivatives have been prepared under
thermal solvent-free reaction conditions. In all cases, the reaction conditions were
very simple and high-yielding.
Keywords: Carbamate, heterogeneous catalyst, 2-naphthol, N-protected
1-aminoalkyl-2-naphthol, silica perchloric acid (HClO4-SiO2)
INTRODUCTION
Compounds bearing 1,3-amino-oxygenated functional motifs are
ubiquitous to a variety of biologically important natural products and
potent drugs, including a number of nucleoside antibiotics and HIV
protease inhibitors, such as ritonavir and lipinavir.[1] It is noteworthy that
N-protected 1-aminoalkyl-2-naphthols can be converted to important
biologically active 1-aminomethyl- 2-naphthol derivatives by amide
hydrolysis reaction. The hypotensive and bradycardiac effects of these
compounds have been evaluated.[2]
It is noteworthy that aminotetraline derivatives manifest a number
of important and therapeutically useful biological activities such as
Received August 29, 2008.
Address correspondence to Hamid Reza Shaterian, Department of Chemistry,
Faculty of Sciences, University of Sistan and Baluchestan, P. O. Box 98135-674,
Zahedan, Iran. E-mail: hrshaterian@hamoon.usb.ac.ir
2560

N-Protected 1-Aminoalkyl-2-naphthol
2561
Scheme 1. One-pot preparation of N-protected 1-aminoalkyl-2-naphthol derivatives
using silica perchloric acid (HClO4-SiO2) as catalyst.
antidepressant, immunomodulating and antitumor activities.[3] Despite
this broad range of applications, only a few members of this family of
compounds have been reported. The development of new methods for
their assembly is therefore of considerable synthetic importance.[4]
Recently, we have reported the reaction of 2-naphthol, aromatic
aldehyde, and amides in the presence of silica-supported perchloric acid
(HClO4-SiO2) to form amidoalkyl naphthol derivatives. The reaction pro-
ceeds through the in situ formation of ortho-quinone methides (o-QMs),
and amide acted as a nucleophile. Carbamates instead of amides in the
reaction produced N-protected 1-aminoalkyl-2-naphthols. Carbamates,
which can be deprotected more easily than the amide group,[5] are impor-
tant for preparation of biologically active 1-aminomethyl-2-naphthol
derivatives.[3,4] Silica-supported perchloric acid as a recyclable solid acid
catalyst was prepared from the reaction of silica gel with perchloric acid.
The catalyst has been used in some organic reactions.[6]
With the aim of developing more efficient synthetic processes, we
herein describe a practical, inexpensive method for the preparation of
new N-protected 1-aminoalkyl-2-naphthol derivatives via three-component
condensation reaction of aryl aldehydes, 2-naphthol, and carbamates in the
presence of silica-supported perchloric acid as catalyst under thermal
solvent-free conditions (Scheme 1).
RESULTS AND DISCUSSION
To choose the optimal conditions, first we tried to prepare methyl
(2-hydroxynaphthalen-1-yl)(phenyl)methyl carbamate from the reaction
of benzaldehyde (1 equiv.), 2-naphthol (1 equiv.), and methyl carbamate
(1.2 equiv.) as a model in the absence and also presence of a catalyst
under thermal solvent-free conditions (Table 1). As shown from
Table 1, this transformation requires a catalyst, and the best result was

2562
H. R. Shaterian, A. Hosseinian, and M. Ghashang
Table 1. Optimization amount of HClO4-SiO2 and reaction temperature for
preparation of methyl (2-hydroxynaphthalen-1-yl)(phenyl)methylcarbamate under
thermal solvent-free conditions
Entry
Catalyst (mol%)a
Temperature (ꢀC)
Time (min)
Yield (%)b
1
2
3
4
5
6
1.5
2.5
3.5
5.0
3.5
3.5
110
110
110
110
75
4.0
3.0
2.5
2.5
6.0
5.0
75
83
85
82
77
90
85
a0.07 g of HClO4-SiO2 equal to 0.035 mmol of Hþ, and the molar ratio of the
catalyst to substrate is 3.5 mol%.
bYields refer to the isolated pure product, and the molar ratio of benzaldehyde=
2-naphthol=methyl carbamate is 1=1=1.2.
obtained by carrying out the reaction using 3.5 mol% (0.07 g, 0.035 mmol
Hþ)[6a] of HClO4-SiO2 at 85ꢀC under solvent-free conditions (Table 1).
Using these optimized reaction conditions, the scope and efficiency
of these procedures were explored for the synthesis of a wide variety of
new and novel substituted N-protected 1-aminoalkyl-2-naphthols using
various aryl aldehydes, 2-naphthols, and methyl=benzyl carbamates.
The results are summarized in Table 2.
As shown in Table 2, the direct three-component reactions worked
well with a variety of aryl aldehydes including those bearing electron-
withdrawing and electron-donating groups such as OMe, Cl, F, and
NO2, and the desired compounds were obtained in good yields.
Under the same conditions, this reaction almost could not be
observed when the aliphatic compounds such as propionaldehyde
(Table 2, entry 8) and 2-pyridinecarbaldehyde (Table 2, entry 9) were used
as a starting material.
As reported in literature,[6f] the reaction of 2-naphthol with aromatic
aldehydes in the presence of an acidic catalyst is known to give o-QMs.
The same o-QMs, generated insitu, have been reacted with carbamate
to form N-protected 1-aminoalkyl-2-naphthol derivatives (Scheme 2).
In the absence of the catalyst, no reactions occurred, and all of
staring of materials was intact. Gas chromatography (GC) and thin-layer
chromatography (TLC) verified this phenomenon. Thus, this evidence
confirms that a catalyst is needed to drive each step of the reactions.
Although these compounds have an unsymmetrical center and seems
to show optical activity, the formation of o-QMs with planar structure in
the reaction processes cause preparation of racemic mixtures, and none of
the products would have any optical activity in the polarimeter instrument.

2563

2564

2565

2566

N-Protected 1-Aminoalkyl-2-naphthol
2567
Scheme 2. Suggested mechanism for preparation of N-protected 1-aminoalkyl-2-
naphthol.
When a heterogeneous catalyst was used, an important issue is the
deactivation, reusability, and recyclability of the catalyst because of the
possibility of recycling the catalyst, especially for large-scale operations.
To test this, a series of five consecutive runs of the reaction of benzalde-
hyde, 2-naphthol, and methyl carbamate with the silica perchloric as cat-
alyst were carried out (Table 2, entry 1). When the reaction was complete,
the catalyst was recovered and reused for the same reaction. For this pur-
pose, the catalyst was recovered after each run, washed with ethanol,
dried in an oven at 100ꢀC for 30 min prior to use, and tested for its activ-
ity in the subsequent run. Fresh catalyst was not added. The solid catalyst
was tested for five runs and recycled in 92% average yield. It demon-
strates that there is no significant change in the activity of the catalyst
and no significant loss of product yield. Furthermore, there is no change
in the infrared spectroscopy (IR) of the fresh catalyst and the catalyst
after its fifth use; this indicates that no loss of any organic functionality
has taken place during repeated chemical reactions. Thus, this makes the
process still more cost-effective.
CONCLUSION
In conclusion, we have developed a novel and highly efficient methodol-
ogy for the synthesis of new and novel N-protected 1-aminoalkyl-2-
naphthol derivatives from arylaldehydes, 2-naphthol, and methyl=benzyl
benzyl carbamate under solvent-free conditions.
EXPERIMENTAL
All reagents were purchased from Merck and Aldrich and are used
without further purification. Silica perchloric acid was prepared accord-
ing to the reported procedure.[6a] All yields refer to isolated products after
purification. Products were characterized by spectroscopic data (IR,

2568
H. R. Shaterian, A. Hosseinian, and M. Ghashang
NMR spectra) and melting points with authentic samples. The NMR
spectra were recorded on a Bruker Avance DEX-300 MHz instrument.
Elemental analyses for C, H, and N were performed using a Heraeus
CHN-O-Rapid analyzer. The spectra were measured in dimethyl sulfoxide
(DMSO-d6) relative to tetramethylsilane (TMS) (0.00 ppm). IR spectra
were recorded on a Jasco Fourier transform (FT)–IR 460þ spectrophot-
ometer. All of the compounds were solid, and solid-state IR spectra were
recorded using the KBr disk technique. Mass spectra (MS) were recorded
on an Agilent Technologies 5973 network mass selective detector (MSD)
operating at an ionization potential of 70 eV. Melting points were deter-
mined in open capillaries with a Buchi 510 melting-point apparatus.
TLC was performed on silica-gel polygram SIL G=UV 254 plates.
Preparation of SiO2-HClO4
We prepared SiO2-HClO4 according to the procedure first reported by
Chakraborti and coworkers.[6a] HClO4 (1.25 g, 12.5 mmol, as a 70% aqu-
eous solution) was added to the suspension of silica gel (23.75 g, 230–400
mesh) in Et2O. The mixture was concentrated, and the residue was heated
at 100ꢀC for 72 h under vacuum to afford HClO4-SiO2 (0.5 mmol gꢁ1).
The amount of Hþ in the SiO2-HClO4 was determined by acid–base
titration according to the following reaction [Eq. (1)]:
SiO2-HClO4 þ H2O ꢁ! SiO2-ClOꢂ4 þ H3Oꢃ
ð1Þ
The librated H3Oþ was titrated by standard NaOH, and the amount
of Hþ in SiO2-HClO4 was calculated (1 g of SiO2-HClO4 equal to
0.5 mmol Hþ).
General Procedure for Preparation of N-Protected
1-Aminoalkyl-2-naphthol Derivatives
Silica-supported perchloric acid (0.07 g, 0.035 mmol Hþ)[6a] was added
to a mixture of 2-naphthol (1 mmol), aldehydes (1 mmol), and methyl=
benzyl carbamate (1.2 mmol). The mixture was stirred at 85ꢀC in an oil
bath, and the reaction was followed by TLC. After completion, the
mixture was cooled at room temperature, and then the solid was isolated
and dissolved in EtOH. The catalyst was collected by filtration and
washed with ethanol (3 ꢄ 10 ml), while the filtrate was concentrated
under reduced pressure to furnish the crude product. The solid crude
product was purified by recrystallization from aqueous EtOH (20%).
Spectral data of the products are given in the next section.

N-Protected 1-Aminoalkyl-2-naphthol
Data
2569
Methyl (2-Hydroxynaphthalen-1-yl)(phenyl)methyl Carbamate
(Table 2, entry 1)
1H NMR (300 MHz, DMSO-d6): d ¼3.57 (s, 3H), 6.87 (d, J ¼ 8.4 Hz, 1H),
7.18–7.29 (m, 7H), 7.38 (d, J ¼ 7.4 Hz, 1H), 7.65–7.84 (m, 3H), 7.92
(d, J ¼ 7.7 Hz, 1H), 10.12 (s, 1H, OH) ppm; 13C NMR (75 MHz,
DMSO-d6): d ¼ 50.8, 52.1, 118.9, 119.3, 123.0, 123.5, 126.5, 126.8,
127.0, 128.6, 128.8, 129.0, 129.8, 132.5, 142.8, 153.4, 157.0 ppm; IR
(KBr, cmꢁ1): 3423, 3202, 1677, 1630, 1585, 1518, 1438, 1335, 1272,
1066, 1042, 937, 811, 743, 697; MS (EI, 70 eV): m=z (%) ¼ 307 (Mþ, 13),
295 (9), 279 (15), 232 (79), 231 (100), 202 (16), 167 (31), 149 (76), 115
(10), 104 (10), 71 (14), 57 (18), 43 (10). Anal. calcd. for C19H17NO3: C,
74.25; H, 5.58; N, 4.56%. Found: C, 74.23; H, 5.57; N, 4.52%.
Methyl (2-Hydroxynaphthalen-1-yl)(4-nitrophenyl)methyl
Carbamate (Table 2, entry 2)
1H NMR (300 MHz, DMSO-d6): d ¼ 3.60 (s, 3H), 6.95 (d, J ¼ 8.3 Hz, 1H),
7.22 (d, J ¼ 8.8 Hz, 1H), 7.28 (t, J ¼ 7.2 Hz, 1H), 7.39 (d, J ¼ 7.7 Hz, 1H),
7.47 (d, J ¼ 8.5 Hz, 2H), 7.78–7.87 (m, 4H), 8.15 (d, J ¼ 8.6 Hz, 2H), 10.22
(s, 1H, OH) ppm; 13C NMR (75 MHz, DMSO-d6): d ¼ 50.6, 52.3, 118.4,
118.8, 123.1, 123.3, 123.8, 127.3, 127.6, 128.8, 129.1, 130.4, 132.4, 146.5,
151.2, 153.6, 157.2 ppm; IR (KBr, cmꢁ1): 3422, 3265, 1683, 1628, 1604,
1518, 1438, 1346, 1272, 1247, 1068, 1046, 852, 823, 782, 741, 704; MS
(EI, 70 eV): m=z (%) ¼ 352 (Mþ, 17), 276 (21), 260 (85), 231 (36), 230
(100), 202 (25), 115 (10). Anal. calcd. for C19H16N2O5: C, 64.77; H,
4.58; N, 7.95%. Found: C, 64.75; H, 4.58; N, 7.91%.
Methyl (4-Chlorophenyl)(2-hydroxynaphthalen-1-yl)methyl
Carbamate (Table 2, entry 3)
1H NMR (300 MHz, DMSO-d6): d ¼ 3.57 (s, 3H), 6.84 (d, J ¼ 8.2 Hz, 1H),
7.20–7.41 (m, 7H), 7.71–7.81 (m, 3H), 7.89 (d, J ¼ 7.3 Hz, 1H, NH), 10.16
(s, 1H, OH) ppm; 13C NMR (75 MHz, DMSO-d6): d ¼ 50.3, 52.1, 118.9,
123.0, 123.4, 127.1, 128.4, 128.5, 128.8, 129.1, 130.0, 131.4, 132.4, 141.9,
153.4, 157.1 ppm; IR (KBr, cmꢁ1): 3422, 3225, 2951, 1685, 1629, 1583,
1516, 1491, 1438, 1330, 1273, 1245, 1182, 1144, 1088, 1014, 963, 852,
807, 749, 708; MS (EI, 70 eV): m=z (%) ¼ 341 (Mþ, 7), 266 (33), 265
(50), 231 (100), 202 (18). Anal. calcd for C19H16ClNO3: C, 66.77; H,
4.72; N, 4.10%. Found: C, 66.71; H, 4.68; N, 4.10%.

2570
H. R. Shaterian, A. Hosseinian, and M. Ghashang
Methyl (2,4-Dichlorophenyl)(2-hydroxynaphthalen-1-yl)methyl
Carbamate (Table 2, entry 4)
1H NMR (300 MHz, DMSO-d6): d ¼ 3.54 (s, 3H), 6.83 (d, J ¼ 8.1 Hz, 1H),
7.13 (d, J ¼ 8.9 Hz, 1H), 7.28 (t, J ¼ 7.3 Hz, 1H), 7.38–7.57 (m, 4H), 7.75
(d, J ¼ 8.7 Hz, 1H), 7.80 (d, J ¼ 8.0 Hz, 1H), 7.92 (d, J ¼ 8.0 Hz, 1H,
NH), 8.01 (d, J ¼ 8.6 Hz, 1H), 9.93 (s, 1H, OH) ppm; 13C NMR
(75 MHz, DMSO-d6): d ¼ 49.9, 52.0, 116.8, 119.0, 122.9, 123.1, 127.0,
127.1, 128.7, 129.0, 129.1, 130.2, 131.7, 132.4, 133.0, 133.6, 139.3, 154.0,
156.6 ppm; IR (KBr, cmꢁ1): 3404, 3259, 1677, 1626, 1620, 1469, 1437,
1319, 1273, 1236, 1190, 1054, 1035, 815, 853; MS (EI, 70 eV): m=z
(%) ¼ 376 (Mþ, 1), 375 (6), 267 (59), 266 (33), 265 (100), 231 (18), 202
(14), 115 (10), 101 (6). Anal. calcd. for C19H15Cl2NO3: C, 60.65; H,
4.02; N, 3.72%. Found: C, 60.61; H, 4.04; N, 3.75%.
Methyl (3-Chlorophenyl)(2-hydroxynaphthalen-1-yl)methyl
Carbamate (Table 2, entry 5)
1H NMR (300 MHz, DMSO-d6): d ¼ 3.58 (s, 3H), 6.86 (d, J ¼ 8.6 Hz, 1H),
7.13–7.31 (m, 6H), 7.41 (t, J ¼ 7.6 Hz, 1H), 7.77–7.83 (m, 3H), 7.92 (d,
J ¼ 8.0 Hz, 1H, NH), 10.19 (s, 1H, OH) ppm; 13C NMR (75 MHz,
DMSO-d6): d ¼ 50.4, 52.2, 118.7, 118.9, 123.1, 123.3, 125.3, 126.2,
126.8, 127.2, 128.8, 129.1, 130.1, 130.5, 132.4, 133.3, 145.6, 153.4,
157.1 ppm; IR (KBr, cmꢁ1): 3417, 3293, 3070, 1688, 1628, 1596, 1572,
1516, 1474, 1438, 1335, 1274, 1241, 1190, 1045, 808, 748; MS (EI,
70 eV): m=z (%) ¼ 341 (Mþ, 20), 265 (40), 231 (100), 202 (18), 170 (5),
115 (11), 59 (8). Anal. calcd. for C19H16ClNO3: C, 66.77; H, 4.72; N,
4.10%. Found: C, 67.02; H, 4.75; N, 4.11%.
Methyl (2-Hydroxynaphthalen-1-yl)(3-nitrophenyl)methyl
Carbamate (Table 2, entry 6)
1H NMR (300 MHz, DMSO-d6): d ¼ 3.60 (s, 3H), 6.96 (d, J ¼ 8.6 Hz, 1H),
7.22 (d, J ¼ 8.9 Hz, 1H), 7.30 (t, J ¼ 7.3 Hz, 1H), 7.43 (t, J ¼ 7.6 Hz, 1H),
7.55 (t, J ¼ 7.8 Hz, 1H), 7.63 (d, J ¼ 7.8 Hz, 1H), 7.79–7.97 (m, 4H), 8.07
(d, J ¼ 8.0 Hz, 1H, NH), 8.12 (s, 1H) 10.23 (s, 1H, OH) ppm; 13C NMR
(75MHz, DMSO-d6): d ¼ 50.5, 52.3, 118.3, 118.9, 121.0, 122.0, 123.0,
123.1, 127.3, 128.8, 129.1, 130.2, 130.4, 132.4, 133.3, 145.5, 148.2, 153.6,
157.2 ppm; IR (KBr, cmꢁ1): 3389, 3290, 3088, 1687, 1630, 1578, 1525,
1440, 1340, 1278, 1246, 1138, 1044, 923, 806, 733, 634; MS (EI, 70eV):
m=z (%) ¼ 352 (Mþ, 28), 335 (18), 295 (40), 277 (33), 276 (57), 260 (87),

N-Protected 1-Aminoalkyl-2-naphthol
2571
231 (80), 230 (100), 202 (39), 149 (12), 115(15). Anal. calcd. for C19H16N2O5:
C, 64.77; H, 4.58; N, 7.95%. Found: C, 64.80; H, 4.57; N, 7.92%.
Methyl (2,5-Dimethoxyphenyl)(2-hydroxynaphthalen-1-yl)methyl
Carbamate (Table 2, entry 7)
1H NMR (300MHz, DMSO-d6): d ¼ 3.54 (s, 3H), 3.56 (s, 3H), 3.64 (s, 3H),
6.73 (d, J ¼ 8.8 Hz, 1H), 6.81 (d, J ¼ 8.8 Hz, 1H), 7.02 (d, J ¼ 9.1 Hz, 1H),
7.17 (d, J ¼ 8.9 Hz, 2H), 7.27 (t, J ¼ 7.0 Hz, 1H), 7.43–7.54 (m, 2H), 7.72
(d, J ¼ 8.8 Hz, 1H), 7.77 (d, J ¼ 8.1 Hz, 1H), 8.24 (d, J ¼ 8.6 Hz, 1H,
NH), 10.07 (s, 1H, OH) ppm; 13C NMR (75 MHz, DMSO-d6): d ¼ 47.1,
51.9, 55.7, 56.4, 111.9, 112.2, 116.0, 119.1, 119.2, 122.8, 123.7, 126.5,
128.6, 128.7, 129.4, 131.8, 132.8, 151.0, 153.2, 153.5, 156.4 ppm; IR (KBr,
cmꢁ1): 3403, 3245, 3019, 2952, 2908, 1679, 1626, 1578, 1526, 1498, 1405,
1307, 1296, 1245, 1194, 1090, 856, 818, 750, 719; MS (EI, 70eV): m=z
(%) ¼ 367 (Mþ, 7), 335 (16), 262 (42), 261 (100), 218 (18). Anal. calcd. for
C21H21NO5: C, 68.65; H, 5.76; N, 3.81%. Found: C, 68.58; H, 5.75;
N, 3.83%.
Benzyl (2-Hydroxynaphthalen-1-yl)(phenyl)methyl Carbamate
(Table 2, entry 10)
1H NMR (300 MHz, DMSO-d6): d ¼ 5.04 (d, J ¼ 12.5 Hz, 1H), 5.11 (d,
J ¼ 12.5 Hz, 1H), 6.92 (d, J ¼ 8.6 Hz, 1H), 7.16–7.36 (m, 13H), 7.76–7.82
(m, 3H), 7.92 (d, J ¼ 7.5 Hz, 1H, NH), 10.13 (s, 1H, OH) ppm; 13C
NMR (75 MHz, DMSO-d6): d ¼ 50.8, 66.1, 118.9, 119.3, 122.9, 126.5,
126.8, 126.9, 128.2, 128.6, 128.8, 128.9, 129.0, 129.8, 132.5, 137.5, 142.8,
153.4, 156.5 ppm; IR (KBr, cmꢁ1): 3423, 3200, 3064, 3034, 1675, 1629,
1581, 1514, 1438, 1328, 1271, 1221, 1132, 1040, 943, 808, 753, 697; MS
(EI, 70 eV): m=z (%) ¼ 383 (Mþ, 7), 281 (9), 232 (74), 231 (100), 202
(13), 115 (9), 91 (47). Anal. calcd. for C25H21NO3: C, 78.31; H, 5.52; N,
3.65%. Found: C, 78.25; H, 5.69; N, 3.64%.
Benzyl (2-Chlorophenyl)(2-hydroxynaphthalen-1-yl)methyl
Carbamate (Table 2, entry 11)
1H NMR (300 MHz, DMSO-d6): d ¼ 5.02 (d, J ¼ 12.7 Hz, 1H), 5.10 (d,
J ¼ 12.9 Hz, 1H), 6.95 (d, J ¼ 8.0 Hz, 1H), 7.17 (d, J ¼ 8.7 Hz, 1H),
7.24–7.53 (m, 11H), 7.76 (d, J ¼ 9.1 Hz, 1H), 7.81 (d, J ¼ 8.1 Hz, 1H,
NH), 8.04 (t, J ¼ 8.1 Hz, 2H), 9.96 (s, 1H, OH) ppm; 13C NMR
(75 MHz, DMSO-d6): d ¼ 50.2, 65.8, 117.4, 119.0, 122.8, 123.4, 126.8,

2572
H. R. Shaterian, A. Hosseinian, and M. Ghashang
127.0, 127.9, 128.1, 128.7, 128.9, 129.1, 129.8, 130.0, 130.4, 133.0, 133.1,
137.6, 139.8, 154.0, 156.1 ppm; IR (KBr, cmꢁ1): 3421, 3170, 3062, 3030,
1700, 1627, 1579, 1516, 1476, 1437, 1375, 1335, 1274, 1247, 1050, 819,
753, 733; MS (EI, 70 eV): m=z (%) ¼ 417 (Mþ, 7), 282 (12), 232 (32), 231
(100), 202 (12), 115 (8), 91 (61). Anal. calcd. for C25H20ClNO3: C,
71.85; H, 4.82; N, 3.35%. Found: C, 71.65; H, 4.77; N, 3.30%.
Benzyl (3-Chlorophenyl)(2-hydroxynaphthalen-1-yl)methyl
Carbamate (Table 2, entry 12)
1H NMR (300 MHz, DMSO-d6): d ¼ 5.00 (d, J ¼ 12.8 Hz, 1H), 5.08 (d,
J ¼ 12.8 Hz, 1H), 6.93 (d, J ¼ 7.6 Hz, 1H), 7.15 (d, J ¼ 8.6 Hz, 1H),
7.26–7.37 (m, 10H), 7.52 (s, 1H), 7.74–7.81 (m, 2 H), 8.02–8.05 (m, 2H)
9.93 (s, 1H, OH) ppm; 13C NMR (75 MHz, DMSO-d6): d ¼ 50.2, 65.8,
117.4, 119.0, 122.8, 123.4, 126.8, 127.0, 127.9, 128.1, 128.7, 128.9,
129.1, 129.8, 130.0, 130.4, 133.1, 137.6, 139.8, 154.0, 156.1 ppm; IR
(KBr, cmꢁ1): 3421, 3170, 1701, 1628, 1579, 1517, 1438, 1377, 1335,
1275, 1248, 1050, 940, 819, 753, 734, 694, 530; MS (EI, 70 eV): m=z
(%) ¼ 417 (Mþ, 4), 415 (6), 295 (8), 282 (6), 232 (22), 231 (100), 202
(13), 115 (8), 91 (40), 77 (7). Anal. calcd. for C25H20ClNO3: C, 71.85;
H, 4.82; N, 3.35%. Found: C, 71.82; H, 4.85; N, 3.33%.
Benzyl (2-Hydroxynaphthalen-1-yl)(3-methoxyphenyl)methyl
Carbamate (Table 2, entry 13)
1H NMR (300MHz, DMSO-d6): d ¼ 3.66 (s, 3H), 5.03 (d, J ¼ 12.6 Hz, 1H),
5.11 (d, J ¼ 12.6 Hz, 1H), 6.74–6.88 (m, 4H), 7.13–7.35 (m, 9H), 7.74–7.81
(m, 3H), 7.90 (d, J ¼ 7.9 Hz, 1H, NH), 10.06 (s, 1H, OH) ppm; 13C NMR
(75 MHz, DMSO-d6): d ¼ 50.7, 55.3, 66.1, 111.6, 112.8, 118.9, 119.2, 122.9,
123.6, 126.9, 128.2, 128.8, 129.0, 129.7, 129.8, 132.5, 137.5, 144.5, 153.4,
156.5, 159.6 ppm; IR (KBr, cmꢁ1): 3406, 3274, 3063, 3008, 2945, 1699,
1625, 1609, 1582, 1508, 1454, 1326, 1294, 1244, 1129, 1040, 961, 816, 771,
744; MS (EI, 70 eV): m=z (%) ¼ 413 (Mþ, 10), 278 (14), 262 (62), 261
(61), 232 (21), 231 (100), 91 (62). Anal. calcd. for C26H23NO4: C, 75.53;
H, 5.61; N, 3.39%. Found: C, 75.45; H, 5.58; N, 3.40%.
Benzyl (4-Fluorophenyl)(2-hydroxynaphthalen-1-yl)methyl
Carbamate (Table 2, entry 14)
1H NMR (300 MHz, DMSO-d6): d ¼ 5.04 (d, J ¼ 12.6 Hz, 1H), 5.10 (d,
J ¼ 12.6 Hz, 1H), 6.89 (d, J ¼ 8.3 Hz, 1H), 7.05–7.12 (m, 2H), 7.21–7.35

N-Protected 1-Aminoalkyl-2-naphthol
2573
(m, 10H), 7.76–7.86 (m, 3H), 7.92 (d, J ¼ 8.0 Hz, 1H, NH), 10.2 (s, 1H, OH)
ppm; 13C NMR (75 MHz, DMSO-d6): d ¼ 50.38, 66.2, 115.1, 115.4, 118.9,
119.0, 123.0, 123.5, 127.0, 128.3, 128.4, 128.5, 128.5, 128.9, 129.0, 129.9,
132.4, 137.4, 138.8, 153.4, 156.5, 159.7 ppm; IR (KBr, cmꢀ1): 3424, 3247,
3072, 2968, 1676, 1268, 1562, 1507, 1455, 1438, 1327, 1273, 1219, 1160,
1066, 944, 854, 815, 755, 703; MS (EI, 70 eV): m=z (%) ¼ 401 (Mþ, 6),
250 (77), 249 (100), 220 (11), 91 (57). Anal. calcd. for C25H20FNO3: C,
74.80; H, 5.02; N, 3.49%. Found: C, 74.71; H, 4.97; N, 3.44%.
ACKNOWLEDGMENT
We are thankful to the Sistan and Baluchestan University Research
Council for the partial support of this research.
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