Synthesis of novel thioamidoalkyl- and thiocarbamidoalkyl naphthols via a three-component condensation reaction using heterogeneous catalyst of ferric hydrogensulfate

Article abstract of DOI:10.1080/00397911.2010.526281

Ferric hydrogensulfate [Fe(HSO₄)₃] was used as a suitable heterogeneous catalyst for the one-pot multicomponent reaction of b-naphthol, aromatic aldehydes, and thioamide derivatives to obtain the corresponding thioamidoalkyl naphthols. Various novel thioamidoalkyl naphthols and thiocarbamidoalkyl naphthols were synthesized in good yields from thioacetamide and thiourea. The heterogeneous nature of the catalyst made it reusable for further chemical reactions.Copyright Taylor & Francis Group, LLC.

Full text of DOI:10.1080/00397911.2010.526281

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Synthesis of Novel Thioamidoalkyl-
and Thiocarbamidoalkyl Naphthols
via a Three-Component Condensation
Reaction Using Heterogeneous Catalyst
of Ferric Hydrogensulfate
Hossein Eshghi a , Gholam Hossein Zohuri a & Saman Damavandi a
a Department of Chemistry, Ferdowsi University of Mashhad,
Mashhad, Iran
Accepted author version posted online: 04 Aug 2011.Version of
record first published: 17 Oct 2011.
To cite this article: Hossein Eshghi , Gholam Hossein Zohuri & Saman Damavandi (2012): Synthesis
of Novel Thioamidoalkyl- and Thiocarbamidoalkyl Naphthols via a Three-Component Condensation
Reaction Using Heterogeneous Catalyst of Ferric Hydrogensulfate, Synthetic Communications: An
International Journal for Rapid Communication of Synthetic Organic Chemistry, 42:4, 516-525
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Synthetic Communications1, 42: 516–525, 2012
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397911.2010.526281
SYNTHESIS OF NOVEL THIOAMIDOALKYL- AND
THIOCARBAMIDOALKYL NAPHTHOLS VIA A
THREE-COMPONENT CONDENSATION REACTION
USING HETEROGENEOUS CATALYST OF FERRIC
HYDROGENSULFATE
Hossein Eshghi, Gholam Hossein Zohuri, and
Saman Damavandi
Department of Chemistry, Ferdowsi University of Mashhad, Mashhad, Iran
GRAPHICAL ABSTRACT
Abstract Ferric hydrogensulfate [Fe(HSO4)3] was used as a suitable heterogeneous
catalyst for the one-pot multicomponent reaction of b-naphthol, aromatic aldehydes, and
thioamide derivatives to obtain the corresponding thioamidoalkyl naphthols. Various novel
thioamidoalkyl naphthols and thiocarbamidoalkyl naphthols were synthesized in good yields
from thioacetamide and thiourea. The heterogeneous nature of the catalyst made it reusable
for further chemical reactions.
Keywords Ferric hydrogensulfate; heterogeneous catalyst; multicomponent reaction;
thioacetamide; thioamidoalkyl naphthol
INTRODUCTION
Multicomponent reactions (MCRs) have become an efficient and powerful tool
for the construction of complex molecules because products are formed in a one-pot
reaction without isolation of intermediates or modification the reaction con-
ditions.[1–3] MCRs are particularly useful for generating diverse chemical libraries
of drug-like molecules for biological screening.[4] One-pot reactions provide the
possibility of synthesizing the complex directly, without isolating the intermediates,
which prompts researchers to design such reactions using different catalysts. There-
fore, the reaction times are reduced and both the energy and raw materials are
saved.[5,6]
Received July 1, 2010.
Address correspondence to Hossein Eshghi, Department of Chemistry, Ferdowsi University of
Mashhad, Mashhad 91775-1436, Iran. E-mail: heshghi@ferdowsi.um.ac.ir
516

NOVEL THIOAMIDOALKYL NAPHTHOLS
517
Compounds bearing 1,3-amino oxygenated functional groups are biologically
important natural products and potential drugs, including a number of nucleoside
antibiotics and HIV protease inhibitors, such as ritonavir and lipinavir.[7] Amino-
naphthols have been reported to exhibit antihypertensive, adrenoceptor blocking,
and Caþ2 channel blocking, activities.[8] Furthermore, amidoalkyl naphthols can
be converted to useful synthetic building blocks and 1-aminomethyl-2-naphthols,
which exhibit depressor and bradycardiac activity.[9,10]
Many studies have been devoted to the preparation of amidoalkyl naphthols
by multicomponent condensation of aldehydes, b-naphthol, and amide in the pres-
ence of various Lewis or Brønsted acid catalysts.[11–18] However, to the best of our
knowledge, only two works with limited examples have reported on the replacement
of amide with thioamide or thiourea.[19,20]
In the present study, ferric hydrogenesulfate [Fe(HSO4)3] was introduced as an
efficient catalyst for synthesis of the thioamidoalkyl naphthols and thiocarbami-
doalkyl naphthols by one-pot, three-component coupling of b-naphthol, aromatic
aldehydes, and thioacetamide or thiourea (Scheme 1).
Synthesis of thioamidoalkyl and thiocarbamidoalkyl naphthols was performed
successfully by the three-component condensation of b-naphthol, aryl aldehydes,
and thiourea or thioacetamide in the presence of heterogeneous catalyst of ferric
hydrogenesulfate.[21] To find the optimum conditions, the one-pot reaction of men-
tioned components was carried out in different conditions. First of all, one-pot,
three-component reaction of b-naphthol, 4-nitrobenzaldehyde, and thiourea in the
presence of ferric hydrogenesulfate was carried out as an experimental model with
different solvents, while the reaction time and the amount of used catalyst were kept
constant.
As it can be seen in Table 1, the greatest yield was obtained using dimethylsulf-
oxide (DMSO) as a solvent. Because of the good yield and easier workup procedure,
1,2-dichloroethane was used for further studies of multicomponent reactions. It
should be noted that the model reaction was carried out with three different amounts
of catalyst to find the optimum molar ratio of the catalyst (Table 1). However,
addition of more than 10% of the catalyst only slightly increased the yield of the
reaction. Thus, further studies were carried out in the presence of 10% molar ratio
of ferric hydrogensulfate as a catalyst.
Our previous study showed that the ferric hydrogensulfate is a durable catalyst
for six subsequent reactions.[22] However, in the present work, reusability of the cata-
lyst was studied in the reaction of b-naphthol, 4-nitrobenzaldehyde, and thiourea in
the presence of the catalyst in 1,2-dichloroethane as a solvent. After completion of
each run, the catalyst was recovered simply. The hydrated catalyst was washed
Scheme 1. Ferric hydrogensulfate–catalyzed three-component synthesis of thioamidoalkyl and thiocarba-
midoalkyl naphthols.

518
H. ESHGHI, G. H. ZOHURI, AND S. DAMAVANDI
Table 1. Influence of the solvent, mol% of the catalyst, and its reusability in the
three-component reaction of b-naphthol, 4-nitrobenzaldehyde, and thioureaa
Entry
Solvent
Catalyst (%)
Yield (%)b
1
2
CH3CN
C2H5OH
CH3OH
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (8)
70
72
3
75
76
c
4
CH2Cl2
c
5
CHCl3
80
95
6
DMSO
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
C2H4Cl2
7
92
85
8
9
Fe(HSO4)3 (5)
80
92
10d
11e
12f
13g
14
15
16
17
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
Fe(HSO4)3 (10)
FeCl3 (10)
92
88
85
20
NaHSO4 (10)
NaHSO4 (30)
Trace
35
62
FeCl3 (10) þ NaHSO4 (30)
aAll reactions were carried out at 60 ꢀC for 8 h.
bIsolated yields.
cReflux condition.
d–gReusability of the recovered catalyst in new runs.
several times with methanol and dried in an oven at 80 ꢀC for 2 h before reusing. As
can be seen in Table 1, the catalyst could be reused without significant loss of its
catalytic activity at least four times.
To find out which part of the catalyst is responsible for promoting the reaction,
we studied this reaction in the presence of catalytic amounts of FeCl3 and NaHSO4.
Comparing the of catalytic efficiency of Fe(HSO4)3 (10%) with NaHSO4 (10% and
30%) and FeCl3 (10%) or combining them showed that ferric hydrogensulfate was
acting even better than a bifunctional catalyst (Table 1, entries 14–17). As can be
seen in Table 1, it seems that both parts of the catalyst are involved in catalyzing
the reaction. It is noteworthy that by monitoring the reaction with thin-layer chro-
matography (TLC), we realized that the ortho-quinone methide (o-QM) intermediate
in the presence of FeCl3 appeared faster than in the reactions using NaHSO4; how-
ever the yield was lower. It is conceivable that the first stage catalyzes better in the
presence of ferric because of chelate formation, but the next stage can be catalyzed
by both of them.
Various aromatic aldehydes, thioacetamide, thiourea, or urea were reacted
with b-naphthol in 1,2-dichloroethane to obtain corresponding thioamidoalkyl
naphthols in good yield using catalytic amount of ferric hydrogensulfate. The results
are illustrated in Table 2. Although aromatic aldehydes bearing either electron-
donating or electron-withdrawing substituted groups reacted successfully and
afforded the products in good yields, reaction times were profoundly varied. As
expected, the aromatic aldehydes with electron-withdrawing groups reacted faster
than the aromatic aldehyde with electron-releasing groups.

NOVEL THIOAMIDOALKYL NAPHTHOLS
519
Table 2. Results of thioamidoalkyl and thiocarbamidoalkyl naphthol synthesis
Catalyst
(%mol)
Time
(h)
Yield
(%)a
MP(ꢀC)
[lit.]
Entry
Aldehyde
Amide
Product
240–242
[not
1
10
10
10
6.5
88
88
89
reported][20]
2
3
6
246–248
243–245
192–194
5.5
4
5
10
12
8
6
79
88
179–181
[180–182][19]
6
12
6
90
175–177
7
8
12
12
5
8
91
83
176–178
136–138
9
12
5.30
83
165–167
(Continued )

520
Entry
10
H. ESHGHI, G. H. ZOHURI, AND S. DAMAVANDI
Table 2. Continued
Catalyst
(%mol)
Time
(h)
Yield
(%)a
MP(ꢀC)
[lit.]
Aldehyde
Amide
Product
10
6
81
202–204
11
12
13
10
10
10
7
7
8
78
75
35
218–220
170–172
185–187
225–227
14
15
10
10
8
25
88
175–176
[174–175][15]
6.5
168–169
[168–169][15]
16
17
10
10
5
5
92
94
179–180
[181–182][14]
(Continued )

NOVEL THIOAMIDOALKYL NAPHTHOLS
521
Table 2. Continued
Catalyst
(%mol)
Time
(h)
Yield
(%)a
MP(ꢀC)
[lit.]
Entry
18
Aldehyde
Amide
Product
186–187
[184–186][11]
10
8
84
aIsolated yields.
The adopted mechanism[11] in the synthesis of amidoalkyl naphthol com-
pounds is outlined in Scheme 2 for thio derivatives: in situ generation of ortho-
quinone methides (o-QMs) and addition of thioamide to form thioamidoalkyl
naphthol derivatives. In fact, the nucleophilicity of nitrogen atoms of thiourea or
thioacetamide is very weak because of the push–pull effect, which increases the
nucleophilicity of sulfur atoms. We suggest that sulfur can attack kinetically to
o-QMs, but reversibility of the reaction (unstable product) in this case favored attack
by nitrogen to form a thermodynamically stable product. Beside, the interaction of
o-QMs with Fe(HSO4)3 increases its hardness and provides a condition for the attack
of the hard nitrogen (weak nucleophile) rather than soft sulfur (strong nucleophile)
attack. Because the reactions of b-naphthol, aldehydes, and thiourea failed in the
[23]
presence of some reported catalysts such as I2 and oxalic acid,[24] we suggest that
the second stage is an acid-catalyzed nucleophilic substitution.
The poor reaction with heterocyclic aldehydes can be explained by low cata-
lytic activation of the furfural carbonyl group by acid because conjugation with
the heterocyclic heteroatom lowers the carbonyl carbon’s electrophilicity. Many stu-
dies reported obtaining only trace amounts of the corresponding products in the
reaction of heterocyclic aldehydes such as pyridine-4-carboxaldehyde, indole-3-
carboxaldehyde, and furfural with 2-naphthol and acetamide.[2,4,11] However, in
the presence of ferric hydrogensulfate, the corresponding products in the reaction
of furfural, b-naphthol, and thioacetamide or thioamide were obtained in better
yields (Table 2, entries 13 and 14).
In conclusion, we have elaborated an efficient, simple, and mild one-pot
procedure for the synthesis of thioamidoalkyl and thiocarbamidoalkyl naphthol
Scheme 2. Proposed mechanism for thioamidoalkyl naphthol synthesis.

522
H. ESHGHI, G. H. ZOHURI, AND S. DAMAVANDI
derivatives. This new approach provided moderate to good yield of products with
the simple experimental and workup procedure. Since the Fe(HSO4)3 catalyst is an
inexpensive, easy to produce and handle, and readily removable and reusable, our
method seems to be attractive process for the convenient synthesis of substituted
thioamidoalkyl and thiocarbamidoalkyl naphthols through a three-component
reaction.
EXPERIMENTAL
Chemicals were either prepared in our laboratories or purchased from
Merck, Fluka, and Aldrich Chemical Companies. All yields refer to isolated pro-
ducts. The reactions were monitored by thin-layer chromatography (TLC) carried
out on silica plates. The products were characterized by comparison of their physical
data with those of known samples or by their spectral data. Infrared (IR) spectra
1
were recorded on a Shimadzu IR 470 spectrophotometer. H NMR spectra was
recorded on a Bruker 100-MHz spectrometer in dimthylsulfoxide (DMSO) as the
solvent and tetramethylsilane (TMS) as internal standard. Elemental analyses were
obtained on a Thermo Finnigan Flash EA microanalyzer. Silica gel 60 (230–400
mesh) was purchased from Merck. Ferric hydrogensulfate was prepared according
to previously reported procedure.[21,22]
General Procedure to Synthesize Thioamidoalkyl and
Thiocarbamidoalkyl Naphthols
Aldehyde (1 mmol), thioacetamide or thiourea (1.2 mmol), and ferric hydro-
gensulfate [Fe(HSO4)3] (10 mol%) were added successively to a mixture of b-naph-
thol (1 mmol) in 1,2-dichloroethane (10 mL). The mixture was stirred at 60 ꢀC, and
the reaction was followed by TLC. After completion of the reaction, the catalyst
was simply recovered through filtration. The hydrated catalyst was washed several
times with methanol and dried in oven at 80 ꢀC for 2 h before reuse. The solvent
was evaporated, and the solid residue was washed with chloroform and water sev-
eral times respectively to obtain the almost pure thioamidoalkyl and thiocarbami-
doalkyl naphthols. For preparation with high purity for elemental analysis, the
final product was purified by short column chromatography (eluent; hexane–ethyl
acetate 4:1).
Spectral Data of the Prepared Compounds
Entry 1. 1H NMR (100 MHz, DMSO-d6): 9.95 (br, 1H), 8.50–8.45 (ss, 1H),
7.85–7.75 (m, 4H), 7.35–7.15 (m, 8H), 1.75 (s, 3H); IR (KBr, cmꢁ1): 3396, 3137,
=
2681, 1590, 1461, 1388 (C S), 1072 (C S), 744. Anal. calcd. for C19H17NOS: C,
=
74.23; H, 5.57; N, 4.56; S, 10.43. Found: C, 74.32; H, 5.59; N, 4.59; S, 10.45.
Entry 2. 1H NMR (100 MHz, DMSO-d6): 10.35 (br, 1H), 8.55–8.50 (ss, 1H),
7.95–7.85 (m, 3H), 7.65–7.55 (m, 3H), 7.35–7.20 (m, 7H), 6.50 (s, 1H); IR (KBr, cmꢁ1):
=
=
3426, 2064, 1519, 1377 (C S), 1086 (C S), 805. Anal. calcd. for C19H16ClNOS: C,
66.75; H, 4.72; N, 4.10; S, 9.38. Found: C, 66.83; H, 4.79; N, 4.17; S, 9.30.

NOVEL THIOAMIDOALKYL NAPHTHOLS
523
Entry 3. 1H NMR (100 MHz, DMSO-d6): 10.08 (br, 1H), 8.30 (s, 1H),
8.05–7.90 (m, 4H), 7.70–7.60 (m, 4H), 7.40–7.25 (m, 5H), 6.75 (s, 1H); IR (KBr,
cmꢁ1): 3369, 3262, 3162, 1598, 1468, 1421 (C S), 1087 (C S), 740. Anal. calcd.
for C19H16N2O3S: C, 64.76; H, 4.58; N, 7.95; O, 13.62; S, 9.10. Found: C, 64.72;
H, 4.69; N, 8.05; S, 9.17.
=
=
Entry 4. 1H NMR (100 MHz, DMSO-d6): 10.12 (br, 1H), 8.15 (s, 1H),
7.95–7.80 (m, 3H), 7.75–7.60 (m, 4H), 7.40–7.25 (m, 6H), 6.55 (s, 1H), 3.55 (s,
3H); IR (KBr, cmꢁ1): 3292, 3085, 2647, 1480 (C S), 1381(C S), 970. Anal. calcd.
for C20H19NO2S: C, 71.19; H, 5.68; N, 4.15; O, 9.48; S, 9.50. Found: C, 71.25; H,
5.74; N, 4.08; S, 9.54.
=
=
Entry 5. 1H NMR (100 Hz, DMSO-d6): d 10.25 (br, 1H), 8.25–8.15 (m, 2H),
7.95–7.80 (m, 3H), 7.40–7.25 (m, 10H); IR (KBr, cmꢁ1): 3442, 3310, 1614, 1514,
=
1435 (C S), 1262 (C S), 1173, 811. Anal. calcd. for C18H16N2OS: C, 70.10; H,
=
5.23; N, 9.08; S, 10.40. Found: C, 69.98; H, 5.16; N, 9.03; S, 10.54.
Entry 6. 1H NMR (100 Hz, DMSO-d6): d 10.12 (br, 1H), 8.35–8.30 (ss, 1H),
8.10 (s, 1H), 7.85–7.74 (m, 4H), 7.50–7.10 (m, 8H); IR (KBr, cmꢁ1): 3471, 3285,
=
1605, 1515, 1436 (C S), 1260 (C S), 1144, 807; Anal. calcd. for C18H15ClN2OS:
=
C, 63.06; H, 4.41; N, 8.17, S; 9.35. Found: C, 63.18; H, 4.49; N, 8.28, S; 9.31.
Entry 7. 1H NMR (100 MHz, DMSO-d6): 10.10 (br, 1H), 8.35–8.30 (m, 3H),
7.90–7.75 (m, 2H), 7.50–7.25 (m, 9H), 7.05-6.95 (m, 1H), 2.30 (s, 3H); IR (KBr,
cmꢁ1): 3390, 3149, 1602, 1557, 1386 (C S), 1081 (C S), 883. Anal. calcd. for
C18H15N3O3S: C, 61.18; H, 4.28; N, 11.89; S, 9.07. Found: C, 61.22; H, 4.34; N,
11.95; S, 9.11.
=
=
Entry 8. 1H NMR (100 MHz, DMSO-d6): 11.10 (br, 1H), 8.45–8.40 (ss, 1H),
8.10–7.95 (m, 2H), 7.70–7.60 (m, 6H), 7.30–7.25 (m, 1H), 7.05-6.95 (m, 4H), 3.70 (s,
3H); IR (KBr, cmꢁ1): 3455, 3262, 2054, 1642, 1379 (C S), 1141 (C S), 814. Anal.
calcd. for C19H18N2O2S: C, 67.43; H, 5.36; N, 8.28; S, 9.47. Found: C, 67.40; H,
5.41; N, 8.20; S, 9.52.
=
=
Entry 9. 1H NMR (100 MHz, DMSO-d6): 9.95 (br, 1H), 8.45–8.30 (m, 2H),
7.70–7.60 (m, 3H), 7.30–7.10 (m, 3H), 6.75-6.60 (m, 6H), 3.65 (s, 3H); IR (KBr,
cmꢁ1): 3351, 3231, 1577, 1491, 1413 (C S), 1037 (C S), 865. Anal. calcd. for
C19H18N2O3S: C, 64.39; H, 5.12; N, 7.90; S, 9.05. Found: C, 64.47; H, 5.19; N,
7.97; S, 8.95.
=
=
Entry 10. 1H NMR (500 MHz, DMSO-d6): 10.28 (b, 3H), 7.91 (d, 0.13H, non-
bonded free-NH), 7.90 (dd, 1H, J1 ¼ 7.5 Hz, J2 ¼ 1.5 Hz), 7.76 (dt, 1H, J1 ¼ 7.5 Hz,
J2 ¼ 1.5 Hz), 7.53 (dd, 1H, J1 ¼ 7.5 Hz, J2 ¼ 1.5 Hz), 7.40 (t, 1H, J ¼ 8 Hz), 7.30 (m,
2H), 6.8–7.2 (m, 4H), 3.63 (s, 3H), 2.25 (s, 3H). IR (KBr, cmꢁ1): 3369, 3262,
=
=
3162, 1598, 1468, 1421 (C S), 1087 (C S), 740. Anal. calcd. for C20H19NO3S: C,
67.97; H, 5.42; N, 3.96; S, 9.07. Found: C, 67.92; H, 5.39; N, 4.01; S, 9.01.
1
Entry 11. 1H NMR (500 MHz, DMSO-d6): H NMR (500 MHz, DMSO-d6):
10.88 (b, 2H, OH), 7.91 (d, 1H, J ¼ 7.5 Hz), 7.78 (m, 1H), 7.61 (m, 1H), 7.53 (d, 1H,
J ¼ 7.5 Hz), 7.44 (t, 1H, J ¼ 9 Hz), 7.37 (t, 1H, J ¼ 8.5 Hz), 7.27 (m, 2H), 7.18 (m,
2H), 7.08 (m, 4H), 2.26 (s, 3H). IR (KBr, Cmꢁ1): 3359, 1629, 1525, 1474, 1420

524
H. ESHGHI, G. H. ZOHURI, AND S. DAMAVANDI
=
(C S), 1257, 1067 (C S), 814, 742. Anal calcd. for C23H19NO2S: C, 73.97; H, 5.13;
=
N, 3.75; S, 8.59. Found: C, 73.89; H, 5.02; N, 3.81; S, 8.51.
Entry 12. 1H NMR (100 MHz, DMSO-d6): d 11.30 (bs, 2H), 8.50 (bs, 1H),
6.80–8.25 (m, 12H), 6.50 (s, 1H), 3.75 (s, 3H); IR (KBr, cmꢁ1): 3347, 3180, 1586,
=
1444, 1409 (C S), 1033 (C S), 917. Anal. calcd. for C22H18N2O2S: C, 70.57; H,
=
4.85; N, 7.48; S, 8.56. Found: C, 70.62; H, 4.89; N, 7.53; S, 8.61.
Entry 13. 1H NMR (100 MHz, DMSO-d6): d: 10.20 (br, 1H), 7.92 (bs, 1H),
7.75–7.05 (m, 10H), 6.95–6.90 (m, 2H); IR (KBr, cmꢁ1): 3362, 3099, 1580, 1473,
=
=
1288 (C S), 1011 (C S), 822. Anal. calcd. for C16H14N2O2S: C, 64.41; H, 4.73;
N, 9.39; S, 10.75. Found: C, 64.52; H, 4.79; N, 9.43; S, 10.89.
Entry 14. 1H NMR (100 MHz, DMSO-d6): 10.28 (br, 1H), 8.05 (s, 1H),
7.80–7.70 (m, 3H), 7.45–7.30 (m, 3H), 7.05-6.95 (m, 4H), 2.30 (s, 3H); IR (KBr,
cmꢁ1): 3420, 3095, 1580, 1431, 1265 (C S), 1233, 1119 (C S), 856. Anal. calcd.
for C17H15NO2S: C, 68.66; H, 5.08; N, 4.71; S, 10.78. Found: C, 68.62; H, 5.14;
N, 4.65; S, 10.85.
=
=
AKNOWLEDGMENT
We are thankful to the Ferdowsi University Research Council for the financial
support of this work (Grant P 743:22-10-88).
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