Synthesis of new cardanol and cardol derivatives by allylation and regioselective cyclocarbonylation reactions

Article abstract of DOI:10.1055/s-2002-35983

Palladium acetate [Pd(OAc)₂] and 1,4-bis(diphenylphosphino)butane (dppb) catalyse cyclocarbonylation of allylic cardanol and cardol derivatives to give regioselectively 7-membered ring lactones in good yields. One of the compounds prepared exhibits excellent antioxidant properties.

Full text of DOI:10.1055/s-2002-35983

PAPER
2749
Synthesis of New Cardanol and Cardol Derivatives by Allylation and
Regioselective Cyclocarbonylation Reactions
Cardanol and
C
ar
i
dol De
c
rivatives by
c
A
llylation
a
andRegio
r
selective
d
Cyclocarbon
o
ylation
R
eactions Amorati,a Orazio A. Attanasi,b Bassam El Ali,d Paolino Filippone,*b Giuseppe Mele,c
Jolanda Spadavecchia,c Giuseppe Vasapollo*c
a
Dipartimento di Chimica Organica ‘A. Mangini’, Università di Bologna, Via S. Donato 15, 40127 Bologna, Italy
b
Centro di Studio delle Sostanze Organiche di Origine Naturale, Università di Urbino, Piazza della Repubblica 13, 61029 Urbino, Italy
Dipartimento di Ingegneria dell’Innovazione, Università di Lecce, Via Arnesano, 73100 Lecce, Italy
c
d
Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahram 31261, Saudi Arabia
E-mail: attor@uniurb.it
Received 28 August 2002
and stabilizers, flame retardants, resins, inks, and hydro-
repellents.3
Abstract: Palladium acetate [Pd(OAc)2] and 1,4-bis(diphenylphos-
phino)butane (dppb) catalyse cyclocarbonylation of allylic cardanol
and cardol derivatives to give regioselectively 7-membered ring
lactones in good yields. One of the compounds prepared exhibits
excellent antioxidant properties.
Our interest for the cyclocarbonylation reactions, mainly
devoted to the synthesis of lactones and lactams, prompt-
ed us to examine the possibility to obtain new allylated
and cyclocarbonylated cardanol and cardol derivatives as
suitable precursors for the production of fine chemicals
(anti-oxidants, polymeric precursors, etc.) by regioselec-
tive cyclocarbonylation process catalysed by the
Pd(OAc)2-1,4-bis(diphenylphosphino)butane (dppb) sys-
tem.
Key words: allylations, carbonylations, cardanol, cardol, lactones,
palladium
The chemistry of renewable organic raw materials for the
production of new commercial materials is of topical im-
portance and deserves the attention both of academic and
industrial research. Industrial grade cardanol, as a yellow
oil, is obtained by vacuum distillation of pollutant, dark,
tar-like, and partially polymerised ‘cashew nut shell liq-
uid’ (CNSL), the international name of the alkyl phenolic
oil contained in the spongy mesocarp of the cashew nut
shell (Anacardium occidentale L.). This oil derives as by-
product from the most diffused roasted mechanical pro-
cesses of the cashew industry in view of the high edible
value of the kernels.1,2 CNSL represents nearly 25% of the
total nut weight and its world-wide production (Africa,
Asia, and South America being the main producer areas)
is estimated to be about 300 000 tons per year. Therefore,
CNSL represents an alternative, sustainable, low-cost,
and largely available natural resource. Indeed, the dis-
tilled cardanol is mainly a mixture of 3-n-pentadecylphe-
nol (1) in which the aliphatic side-chain may be saturated,
mono-olefinic (8), di-olefinic (8, 11), and tri-olefinic (8,
11, 14), with an average value of two double bonds per
molecule, together with a minor amount of cardol (3-n-
pentadecylresorcinol) and methyl cardol (2-methyl-5-n-
pentadecylresorcinol). Hydrogenation of the double
bonds in the side-chain of distilled cardanol leads to 3-n-
pentadecylphenol (1) of good industrial grade.
Previously some of us showed that 2-allylphenol in tolu-
ene can undergo cyclocarbonylation reaction in the pres-
ence of the homogeneous catalytic system Pd(OAc)2–
dppb and CO–H2 (1:1) to produce the seven membered
ring lactone as the major product.4,5
When the same reaction is carried out in dichloromethane
the five-membered ring lactone was the main product of
the reaction. Now, we report here that the cyclocarbony-
lation of some allylic cardanol and cardol derivatives oc-
curs under relatively mild conditions, in high yields,
affording the seven membered ring lactone as the major
product.4
3-n-Pentadecylphenol (1) in acetone reacted with allylic
bromides 2a–c in the presence of potassium carbonate to
give the allylic derivatives 3a–c and then compounds
4,5a,b,6 by means of Claisen rearrangement. When 3-n-
pentadecylphenol (1) was reacted with allyl bromide (2a)
a mixture of two isomers 4 and 5a was formed in equimo-
lar amounts. In the reaction with 1-bromo-2-butene (2b),
selective formation of product 5b was observed, whereas
in the reaction of 3-n-pentadecylphenol (1) with cinnamyl
bromide (2c) the sole formation of pure product 6 was ob-
served (Scheme 1).
In previous papers, some of us reported the synthesis and
industrial utilizations of cardanol derivatives as fine
chemicals and intermediates, additives for lubricants and
diesel engine fuels, pour-point depressants, antioxidants
2-tert-Butyl-5-n-pentadecylphenol (7a) and the 2-tert-
amyl-5-n-pentadecylphenol (7b) gave the same reaction
with allylic bromides 2a–c with formation of the ethers
8a–d. Then these compounds were treated under Claisen
conditions affording only pure compounds 9a–c and 10.
In the case of the reaction of 2-tert-butyl-5-n-pentade-
cylphenol (7a) with cinnamyl bromide (2c) only para sub-
stituted phenol derivative 10 was formed, presumably due
to the steric hindrance (Scheme 2).
Synthesis 2002, No. 18, Print: 19 12 2002.
Art Id.1437-210X,E;2002,0,18,2749,2755,ftx,en;P04502SS.pdf.
© Georg Thieme Verlag Stuttgart · New York
ISSN 0039-7881

2750
R. Amorati et al.
OH
PAPER
OH
R2
R1
R1
+
+
Br
Br
C15H31
C15H31
2 a-c
1
7 a-b
2 a-c
K2CO3,
acetone
reflux
K2CO3,
acetone
reflux
O
R1
O
R1
R2
C15H31
3 a-c
C15H31
Claisen
8 a-d
Rearrangement
OH
Claisen
Rearrangement
OH
OH
OH
OH
R1
R1
R2
R2
+
+
R1
C15H31
C15H31
C15H31
+
C15H31
C15H31
5a-b
4
R1
6
R1
3a, 4, 5a R1=H
10
9a-c
3b, 5b
3c, 6
R1=Me
R1=Ph
8a, 9a R1=H
8b, 9b R1=H
8c, 9c R1=Me
8d, 10 R1=Ph
R2=C(CH3)3
R2=C(CH3)2CH2CH3
R2=C(CH3)3
Scheme 1
R2=C(CH3)3
Scheme 2
Allylpentadecylphenol derivatives 4 and 5a, as a mixture,
underwent cyclocarbonylation reactions to give the cyclo-
carbonylated compounds 11 and 12 (Scheme 3, path a).
The same allylphenol derivatives 4 and 5a reacted again
with allyl bromide to form the ethers mixture 13 and 14
and after Claisen rearrangement the bis-allylpentade-
cylphenol 15.
bis-lactones.6 As an extension of the double-carbonyla-
tion reactions previously reported, we applied analogous
reactions to 5-n-pentadecylresorcinol (19) showing two
phenolic OHs in meta positions of the benzene ring.
5-n-Pentadecylresorcinol (19) reacted with two equiva-
lents of allyl bromide (2a) to afford symmetric diallyl
ether 20 that gave double Claisen rearrangment to resorci-
nol derivative 21. This last compound was then treated
with the homogeneous catalytic system Pd (OAc)2–dppb
and CO–H2 (1:1) and the corresponding bis-lactone 22
was formed (Scheme 5).
Cyclocarbonylation reaction of 15 gave a mixture of two
compounds impossible to separate by chromatography,
but GC–MS analysis showed the same molecular weight
and similar fragmentation pattern and could be ascribed to
two isomeric seven-membered, cyclocarbonylated com-
pounds 16 and 17 (Scheme 3, path b).
In agreement with our previous paper,7 we determined
by kinetic measurements (inhibition rate constants kinh
M–1s–1) the antioxidant properties of some allylic deriva-
tives (9a,c) in comparison both with other cardanol deriv-
atives and commercial antioxidants (Table 1).
2-tert-Butyl-6-allyl-5-n-pentadecylphenol (9a) and 2-
tert-amyl-6-allyl-5-n-pentadecylphenol (9b) were reacted
in toluene in the presence of the same catalytic system and
afforded the cyclocarbonylated compounds 18a,b, respec-
tively (Scheme 4).
No influence at all was observed due to the presence of a
bulky substituent in the ortho position of the phenolic hy-
droxyl. Recently, we also investigated the double-carbon-
ylation reactions of bis-allyl derivatives of cardol using
the homogeneous catalytic system Pd (OAc)2–dppb under
relatively mild conditions, for the preparation of various
As can be seen, 3-n-pentadecylphenol (hydrogenated car-
danol) 1 exhibits an antioxidant activity similar to those of
23 and 25 (Irganox 1076, Anox PP 18) . As expected, the
introduction of a tert-butyl group in the ortho position to
the hydroxy function of 1 determines a higher antioxidant
Synthesis 2002, No. 18, 2749–2755 ISSN 0039-7881 © Thieme Stuttgart · New York

PAPER
Cardanol and Cardol Derivatives by Allylation and Regioselective Cyclocarbonylation Reactions
2751
Scheme 3
Table 1 Inhibition Rate Constants for Some Cardanol Derivatives
O
And Commercial Antioxidants
OH
O
Item
23
Compound
kinh/104
2.6
R
R
Pd(OAc)2, DPPB
CO / H2 (1 / 1)
2,6-di-tert-butyl-4-methylphenol (BHT)7
24
2,6-di-tert-butyl-4-methoxyphenol (DB-
14
C15H31 Toluene
600 psi, 120 °C
C15H31
HA)7
9a-b
18a-b
25
octadecyl-3-(3,5-di-tert-butyl-4-hydroxy- 1.5
phenyl)propionate
9a,18a R=C(CH3)3
9b,18b R=C(CH3)2CH2CH3
1
3-n-pentadecylphenol7
1.6
3.2
Scheme 4
7a
9a
9c
2-tert-butyl-5-n-pentadecylphenol7
2-allyl-3-n-pentadecyl-6-tert-butylphenol 1.7
activity of 7a due to the steric hindrance of the tert-butyl
group. The introduction of the allylic group in the second
ortho position of 7a does not increase the antioxidant ac-
tivity of 9a probably due to the modest steric hindrance of
the allyl group, while the introduction of the 1-methylallyl
2-(1-methylallyl)-3-n-pentadecyl-6-tert-
butylphenol
8.7
group in the same position remarkably enhances the anti- high temperatures at which the reticulation process is car-
oxidant activity of 9c in respect to that of the starting com- ried out (ca. 300 °C). It is noteworthy that 9c shows an in-
pound 7a. Due the low volatility, phenolic antioxidants hibition rate constant appreciably higher than that of the
with long alkyl side-chains are very important in the anti- commercial product 25, largely used for the stabilization
oxidative stabilization of some polymers because of the of polymeric materials.8,9
Synthesis 2002, No. 18, 2749–2755 ISSN 0039-7881 © Thieme Stuttgart · New York

2752
R. Amorati et al.
PAPER
O
OH
OH
Claisen
Rearrangement
Br
C15H31
C15H31
C15H31
K2CO3
acetone
reflux
O
OH
OH
19
O
20
21
O
Pd(OAc)2, DPPB
CO / H2 (1 / 1)
C15H31
Toluene
600 psi, 120 °C
O
O
22
Scheme 5
13C NMR (50.32 MHz, CDCl3): = 14.12, 22.70, 29.32, 29.36,
29.52, 29.51, 29.70, 31.36, 31.92, 36.01, 68.68, 111.57, 115.01,
117.51, 121.03, 129.10, 133.47, 144.62, 158.58.
EIMS: m/z (%) = 344 (M+, 19), 161 (12), 148 (100), 147 (46), 133
(44), 107 (35), 91 (16), 57 (9), 43 (23), 41 (32).
In conclusion, the palladium acetate–dppb system cataly-
ses the cyclocarbonylation of allyl derivatives of 3-n-pen-
tadecylphenol and 3-n-pentadecylresorcinol, in the
reported reaction conditions, to give selectively 7-mem-
bered ring lactones in relatively good yields. We have de-
scribed the preparation of various representative
examples of ethers and relevant Claisen rearrangment
products, as well as cyclocarbonylation reactions applied
to cardanol and cardol derivatives to mark the increasing
importance attached to the production of new organic ma-
terials starting from renewable organic resources. In addi-
tion, the compound 9c showed an interesting antioxidant
activity promising for practical utilization.
Anal. Calcd for C24H40O (344.57): C, 83.66; H, 11.70. Found: C,
83.75; H, 11.71.
1-But-2-enyloxy-3-n-pentadecylbenzene (3b)
Yield: 90%; oil
IR (neat): 3028, 2944, 1665, 1621 cm–1.
1H NMR (400 MHz, CDCl3): = 0.98 (t, J = 6.9 Hz, 3 H, CH3), 1.29
(s, 26 H, CH2), 1.78 (d, J = 6.2 Hz, 3 H, CH3), 2.58 (t, J = 7.8 Hz, 2
H, ArCH2), 4.48 (d, J = 5.8 Hz, 2 H, OCH2), 5.85 (m, 1 H, =CH),
6.07 (m, 1 H, =CH), 6.69–6.75 (m, 3 H, Ar), 7.15–7.25 (m, 1 H, Ar).
Most chemicals were used as obtained from commercial sources.
Pd(OAc)2 and dppb are commercially available while allylphenol
derivatives were prepared according to literature procedures.6 Tol-
uene was dried and distilled from sodium under nitrogen. Mps were
13C NMR (100.64 MHz, CDCl3): = 14.25, 18.48, 23.72, 29.78,
29.82, 30.26, 30.45, 30.90, 32.25, 34.13, 120.75, 126.80, 131.65,
135.65, 142.01, 155.62.
taken on an electro thermal apparatus. H and 13C NMR spectra
EIMS: m/z (%) = 358 (M+, 13), 357 (70), 217 (52), 203 (100).
1
were recorded on a Bruker AC-200 or NMR Varian 400 at r.t. and
chemical shifts are reported relative to Me4Si. IR and MS spectra
were performed, respectively, on a Jasco FTIR instrument and a
Hewlett-Packard GC/Mass MSD 5971 instrument. Petroleum ether
refers to the fraction with bp 40–60 °C.
Anal. Calcd for C25H42O (358.61): C, 83.73; H, 11.81. Found: C,
83.61; H, 11.65.
1-n-Pentadecyl-3-(3-phenylallyloxy)benzene (3c)
Yield: 87%; oil.
IR (neat): 3029, 2930, 1612, 1582 cm–1.
Cyclocarbonylation Reactions; General Procedure
1H NMR (400 MHz, CDCl3): = 0.89 (t, J = 7.2 Hz, 3 H, CH3),
1.15–1.68 (m, 26 H, CH2), 2.60 (t, J = 7.6 Hz, 2 H, ArCH2), 4.70 (d,
J = 6.0 Hz, 2 H, OCH2), 6.44 (d, J = 16.0 Hz, 1 H, =CH), 6.75 (d,
J = 16.0 Hz, 1 H, =CH), 6.78–6.90 (m, 3 H, Ar), 7.13–7.22 (m, 1 H,
Ar), 7.25–7.55 (m, 5 H, Ar).
13C NMR (100.64 MHz, CDCl3): = 14.36, 22.94, 29.61, 29.77,
29.83, 29.94, 31.62, 32.17, 36.28, 68.76, 111.87, 115.34, 121.36,
124.91, 126.81, 128.14, 128.81, 129.41, 133.13, 136.77, 144.93,
158.89.
Palladium acetate (0.01 mmol) and dppb (0.04 mmol) were dis-
solved in anhyd toluene (5 mL) and the allyl phenol derivative (1
mmol) was added. The autoclave was purged three times with CO
and pressurised with CO and H2. The reaction mixture was heated
with stirring for 24 h at 100 °C (oil bath temperature). The reaction
mixture was cooled to r.t., the solution was concentrated, and the
residue was extracted with Et2O. The lactones were purified by
chromatography (petroleum ether and Et2O).
1-Allyloxy-3-n-pentadecylbenzene (3a)
Yield: 95%; oil.
EIMS: m/z (%) = 420 (M+, 5), 368 (23), 285 (14), 257 (51), 236
(70), 185 (100).
IR (neat): 3026, 2921, 1600, 1584 cm–1.
Anal. Calcd for C30H44O (420.68): C, 85.65; H, 10.54. Found: C,
85.48; H, 10.49.
1H NMR (200 MHz, CDCl3): = 0.88 (t, J = 6.5 Hz, 3 H, CH3),
1.15–1.60 (m, 26 H, CH2), 2.57 (t, J = 7.5 Hz, 2 H, ArCH2), 4.50–
4.55 (m, 2 H, OCH2), 5.24–5.47 (m, 2 H, =CH2), 5.97–6.17 (m, 1 H,
CH=C), 6.69–6.79 (m, 3 H, Ar), 7.13–7.22 (m, 1 H, Ar).
Synthesis 2002, No. 18, 2749–2755 ISSN 0039-7881 © Thieme Stuttgart · New York

PAPER
Cardanol and Cardol Derivatives by Allylation and Regioselective Cyclocarbonylation Reactions
2753
2-Allyl-3-n-pentadecylphenol (4)
126.36, 127.27, 128.76, 128.86, 130.01, 130.86, 131.07, 137.91,
Yield: 50%; white solid; mp: 63–65 °C.
143.02, 154.23.
IR (neat): 3341, 3075, 2954, 1636, 1580 cm–1.
EIMS: m/z (%) = 420 (M+, 26), 316 (18), 223 (31), 209 (100).
1H NMR (200 MHz, CDCl3): = 0.88 (t, J = 6.5 Hz, 3 H, CH3),
1.11–1.75 (m, 26 H, CH2), 2.60 (t, J = 7.7 Hz, 2 H, ArCH2), 3.47–
3.40 (m, 2 H, ArCH2-allyl), 4.91 (br s, 1 H), 4.99–5.12 (m, 2 H,
=CH2), 5.89–6.09 (m, 1 H, CH=C), 6.66 (d, J = 7.7 Hz, 1 H, Ar),
6.77 (d, J = 7.7 Hz, 1 H, Ar), 7.04 (t, J = 7.7Hz, 1 H, Ar).
Anal. Calcd for C30H44O (420.68): C, 85,65; H, 10.54. Found: C,
85.48; H, 11.62.
2-Allyloxy-1-tert-butyl-4-n-pentadecylbenzene (8a)
Yield 80%; oil.
13C NMR (50.32 MHz, CDCl3): = 14.12, 22.70, 29.36, 29.52,
29.60, 29.66, 29.69, 30.33, 31.31, 31.93, 33.38, 113.40, 115.67,
122.07, 123.21, 127.11, 136.27, 142.81, 154.30.
IR (neat): (3035, 2926, 1632,1595) cm–1.
1H NMR (200 MHz, CDCl3): = 0.98 (t, J = 6.9 Hz, 3 H, CH3), 1.0–
1.70 [m, 26 H, CH2, and 9 H, C(CH3)3], 2.54 (t, J = 6.7 Hz, 2 H,
ArCH2), 4.80–4.85 (m, 2 H, OCH2), 5.25–5.40 (m, 2 H, =CH2),
5.96–6.18 (m, 1 H, CH=C), 6.65–6.70 (m, 2 H ), 7.17 (d, J = 8.0 Hz,
1 H Ar).
13C NMR (50.32 MHz, CDCl3): = 14.12, 22.70, 29.36, 29.49,
29.54, 29.61, 29.66, 29.70, 29.84, 31.40, 31.92, 34.52, 35.66, 68.78,
112.81, 116.80, 120.17, 126.40, 133.75, 135.47, 141.81, 157.25.
EIMS: m/z (%) = 344 (M+, 29), 161(11), 149(12), 148(100).
Anal. Calcd for C24H40O (344.57): C, 83.66; H, 11.70. Found: C,
83.64; H, 11.60.
2-Allyl-5-n-pentadecylphenol (5a)
Yield: 50%; white solid; mp: 68–70 °C.
IR (neat): 3308, 3055, 2953, 2914, 1637, 1575 cm–1.
EIMS: m/z (%) = 400 (M+, 20), 386 (30), 385 (100).
1H NMR (200 MHz, CDCl3): = 0.88 (t, J = 6.5 Hz, 3 H, CH3),
1.00–1.70 (m, 26 H, CH2), 2.52 (t, J = 7.2 Hz, 2 H, ArCH2), 3.37 (d,
J = 6.4 Hz, 2 H, Ar), 4.94 (br s, 1 H, OH, D2O exch.), 5.04–5.21 (m,
2 H, C=CH2 ), 5.90–6.11 (m, 1 H, CH=C), 6.63 (d, J = 1.5 Hz, 1 H,
Ar), 6.70 (dd, J = 1.5, 7.6 Hz, 1 H, Ar), 6.99 (d, J = 7.6 Hz, 1 H, Ar).
Anal. Calcd for C28H48O (400.68): C, 83.93; H, 12.07. Found: C,
83.48; H, 11.82.
2-Allyloxy-1-(1,1-dimethylpropyl)-4-n-pentadecylbenzene (8b)
Yield 78%; oil.
13C NMR (50.32 MHz, CDCl3): =14.10, 22.69, 29.33, 29.36,
29.51, 29.60, 29.65, 29.67, 31.34, 31.92, 34.86, 35.5, 115.79,
116.26, 120.98, 122.26, 130.12, 136.67, 143.11, 153.90.
EIMS: m/z (%) = 344 (M+, 37), 189 (3), 161(10), 149 (12), 148
(100).
IR (neat): 3035, 2926, 1632,1595 cm–1.
1H NMR (400 MHz, CDCl3): = 0.66 (t, J = 7.6 Hz, 3 H, CH3) ,
0,92 (t, J = 6.8 Hz, 3 H, CH3), 1.23–1.43 (m, 30 H, CH2), 1.57–1.66
(m, 2 H), 1.87 (q, J = 7.5 Hz, 2 H, CH2), 2.59 (t, J = 7.5 Hz, 2 H,
CH2), 4.57–4.61 (m, 2 H, OCH2), 5.28–5.32 (m, 1 H, =CH), 5.44–
5.50 (m, 1 H, =CH), 6.08–6.16 (m, 1 H, =CH), 6.70 (d, J = 1.6 Hz,
1 H, Ar), 6.75 (dd, J = 1.6, 7.5 Hz, 1 H, Ar), 7.15 (d, J = 7.5 Hz, 1
H, Ar).
Anal. Calcd for C24H40O (344.57): C, 83.66; H, 11.70. Found: C,
83.69; H, 11.60.
2-(1-Methylallyl)-5-n-pentadecylphenol (5b)
Yield: 82%; white solid; mp: 46–48 °C.
IR (nujol): 3521, 3024, 2925, 1618, 1595 cm–1.
1H NMR (400 MHz, CDCl3): = 0.92 (t, J = 6.8 Hz, 3 H, CH3), 1.30
(m, 26 H, CH2), 1.41 (d, J = 6.8 Hz, 3 H, CH3), 2.68 (t, J = 7.6 Hz,
2 H, ArCH2), 3.90 (m, 1 H, CH), 5.27 (dd, J = 10.0, 1.2 Hz, 1 H,
ArCH), 5.31 (dd, 1 H, J = 16.0, 1.2 Hz, 1 H, =CH), 5.87 (br s, 1 H,
OH, D2O exch.), 6.23 (ddd, J = 16.0, 10.0, 5.6 Hz, 1 H, =CH), 6.77
( d, J = 1.6 Hz, 1 H, Ar), 6.89 (dd, J = 7.6, 1.6 Hz, 1 H, Ar), 7.21(d,
J = 7.6 Hz, 1 H, Ar).
13C NMR (100.64 MHz, CDCl3): = 9.58, 14.11, 22.69, 27.93,
29.37, 29.47, 29.55, 29.62, 29.67, 29.70, 29.87, 31.34, 31.93, 33.25,
35.66, 38.12, 68.89, 112.78, 116.74, 120.15, 127.4, 133.78, 133.85,
141.68, 157.28.
EIMS: m/z (%) = 414 (M+, 5), 385 (100).
Anal. Calcd for C28H48O (414.71): C, 83.99; H,12.15; Found: C,
83.90; H, 12.10.
2-But-2-enyloxy-1-tert-butyl-4-n-pentadecylbenzene (8c)
Yield: 77%; oil
13C NMR (100.64 MHz, CDCl3): = 14.56, 19.36, 23.19, 29.92,
30.16, 30.25, 31.81, 32.46, 35.97, 37.28, 113.99, 116.42, 121.34,
127.99, 128.34, 142.77, 143.11, 153.70.
EIMS: m/z (%) = 358 (M+, 29), 345 (5), 318 (3), 238 (5), 175 (11),
162 (100).
IR (neat): 3035, 2926, 1632,1595 cm–1.
1H NMR (400 MHz, CDCl3): = 0.99 (t, J = 6.8 Hz, 3 H, CH3), 1.48
[s, 9 H, C(CH3)3], 1.35–1.75 (m, 26 H, CH2), 1.81 (d, J = 6.0 Hz, 3
H, CH3), 2.64 (t, J = 7.8 Hz, 2 H, ArCH2), 4.58 (d, J = 5.5 Hz, 2 H,
OCH2), 5.48–6.0 (m, 2 H, =CH), 6.70 (s, 1 H, Ar), 6.79 (d, J = 8.0
Hz, 1 H, Ar), 7.26 (d, J = 8.0 Hz, 1 H, Ar).
13C NMR (100.64 MHz, CDCl3): = 14.58, 18.36, 23.16, 29.82,
30.15, 30.28, 31.86, 32.37, 34.93, 69.02, 113.09, 120.19, 126.56,
126.88, 129.11, 135.64, 141.89, 157.57.
Anal. Calcd for C25H42O (358.61): C, 83.73; H, 11.81. Found: C,
83.57; H, 11.64.
3-n-Pentadecyl-4-(3-phenylallyl)phenol (6)
Yield: 81%; white solid; mp: 62–64 °C.
IR (nujol): 3345, 2924, 1611, 1591 cm–1.
EIMS: m/z (%) = 414 (M+, 15), 399 (15), 360 (28), 345 (100).
Anal. Calcd for C29H50O (414.72): C, 83.99; H, 12.15. Found: C,
85.47; H, 10.81.
1H NMR (400 MHz, CDCl3): = 0.97 (t, J = 6.9 Hz, 3 H, CH3), 1.41
(s, 26 H, CH2), 2.65 (t, J = 7.7, 2 H, ArCH2), 3.55 (d, J = 4.8 Hz, 2
H, ArCH2), 5.50 (br s, 1 H, OH, D2O exch), 6.35–6.46 (m, 2 H,
=CH), 6.70 (dd, J = 8.0, 2.4 Hz, 1 H, Ar), 6.75 (d, J = 2.4 Hz, 1 H,
Ar), 7.11 (d, J = 8.0 Hz, 1 H, Ar), 7.21–7.42 (m, 5 H, Ar).
13C NMR (100.64 MHz, CDCl3): = 14.43, 23.09, 27.24, 29.72,
29.92, 30.05, 30.26, 31.28, 32.27, 33.24, 35.82, 113.16, 116.38,
1-tert-Butyl-4-n-pentadecyl-2-(3-phenylallyloxy)benzene (8d)
Yield: 79%; oil.
IR (neat): 3030, 2930, 1613, 1569 cm–1.
1H NMR (400 MHz, CDCl3): = 0.99 (t, J = 6.9 Hz, 3 H, CH3), 1.37
(s, 26 H, CH2), 1.52 [s, 9 H, C(CH3)3], 2.67 (t, J = 6.7 Hz, 2 H,
ArCH2), 4.82 (d, J = 5.4 Hz, 2 H, OCH2), 6.55 (dt, J = 16, 5.4 Hz, 1
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2-tert-Butyl-5-n-pentadecyl-4-(3-phenylallyl)phenol (10)
Yield: 85%; white solid; mp: 66–68 °C.
IR (nujol): 3510, 2925, 1653, 1599 cm–1.
1H NMR (400 MHz, CDCl3): = 1.15 (t, J = 7.0 Hz, 3 H, CH3), 1.40
(s, 26 H, CH2), 1.57 [s, 9 H, C(CH3)3], 2.67 (t, J = 7.8 Hz, 2 H,
ArCH2), 3.61 (d, J = 5.2 Hz, 2 H, ArCH2), 4.72 (br s, 1 H, OH, D2O
exch), 6.41–6.55 (m, 2 H, =CH), 6.56 (s, 1 H, Ar), 7.21 (s, 1 H, Ar),
7.30 (d, J = 8.0 Hz, 1 H, Ar), 7.39 (t, J = 8.0 Hz, 2 H, Ar), 7.45 (d,
J = 8.0 Hz, 2 H, Ar).
H, =CH), 6.83 (d, J = 7.6 Hz, 1 H, Ar), 6.84 (s, 1 H, Ar), 6.86 (d,
J = 16 Hz, 1 H, =CH), 7.29 (d, J = 7.6 Hz, 1 H, Ar), 7.34 (d, J = 7.2
Hz, 1 H, Ar), 7.42 (t, J = 7.2 Hz, 2 H, Ar), 7.51 (d, J = 7.2 Hz, 2 H,
Ar).
13C NMR (100.64 MHz, CDCl3): = 14.66, 23.24, 29.91, 30.23,
30.43, 31.94, 32.45, 35.04, 69.09, 113.19, 120,55, 125.34, 126.64,
126.76, 128.04, 128.76, 132.48, 135.78, 136.90, 142.05, 157.54.
EIMS: m/z (%) = 476 (M+, 22), 461 (11), 425 (16), 384 (18), 369
(55), 345 (39), 161 (50), 147 (100).
Anal. Calcd for C34H52O (476.79): C, 85.65; H, 10.99. Found: C,
85.47; H, 10.83.
13C NMR (100.64 MHz, CDCl3): = 14.45, 23.08, 27.29, 29.77,
29.99, 30.09, 30.23, 31.35, 32.32, 32.61, 34.53, 36.41, 117.69,
126.40, 127.21, 128.76, 128.81, 129.60, 130.43, 130.64, 133.86,
138.09, 140.12, 152.82.
2-Allyl-6-tert-butyl-3-n-pentadecylphenol (9a)
Yield: 80%; oil.
IR (neat): 3345, 3030, 2930, 1613, 1591 cm–1.
EIMS: m/z (%) = 476 (M+, 27), 425 (30), 423 (33), 369 (31), 345
(100).
1H NMR (200 MHz, CDCl3): 0.95 (t, J = 6.9 Hz, 3 H, CH3), 1.00–
1.16 (m, 26 H, CH2), 1.48 [s, 9 H, C(CH3)3], 2.56 (t, J = 6.7 Hz, 2
H, ArCH2), 3.42–3.45 (m, 2 H, ArCH2), 5.18–5.20 (m, 2 H, =CH2),
5.98–6.07 (m, 1 H, =CH), 7.09 (d, J = 5.5 Hz, 1 H, Ar), 7.12 (d, J =
5.5 Hz, 1 H, Ar).
Anal. Calcd for C34H52O (476.79): C, 85.65; H,10.99. Found: C,
85.60; H, 10.84.
8-n-Pentadecyl-4,5-dihydro-3H-benzo[b]oxepin-2-one (11)
Yield: 95%; white solid; mp 64–65 °C.
13C NMR (50.32 MHz, CDCl3): = 14.12, 22.70, 29.37, 29.52,
29.60, 29.67, 29.69, 29.73, 29.78, 30.91, 31.32, 31.93, 33.68, 34.40,
116.65, 121.27, 123.07, 124.78, 134.33, 136.12, 139.83, 153.66.
EIMS: m/z (%) = 400 (M+, 20), 386 (24), 385 (81), 203 (19) 189
(56), 161 (35), 147 (49), 57 (100).
IR (neat): 3055, 2918, 2851, 1770 cm–1.
1H NMR (200 MHz, CDCl3): = 7.08 (d, J = 7.6 Hz, 1 H), 6.96 (dd,
J = 1.5, 7.6 Hz, 1 H), 6.90 (d, J = 1.5 Hz, 1 H), 2.78 (t, J = 7.2 Hz,
2 H), 2.58 (t, J = 7.5 Hz, 2 H), 2.47 (t, J = 7.2 Hz, 2 H), 2.16 (quint,
J = 7.2 Hz, 2 H), 1.16–1.43 (m, 2 H), 1.40–1.15 (m, 24 H), 0.87 (t,
J = 6.6 Hz, 3 H).
13C NMR (50.32 MHz, CDCl3): = 14.10, 22.68, 29.30, 29.35,
29.50, 29.58, 29.65, 29.66, 29.69, 31.09, 31.78, 35.24, 125.11,
126.86, 128.02, 128.83, 143.46, 151.53, 171.61.
Anal. Calcd for C28H48O (400.68): C, 83.93; H, 12.07. Found: C,
83.47; H, 11.93.
2-Allyl-6-(1,1-dimethylpropyl)-3-n-pentadecylphenol (9b)
Yield: 85%; oil.
IR (neat): 3350, 3028, 2930, 1610, 1590 cm–1.
EIMS: m/z (%) = 372 (37), 317 (10), 176 (12), 175 (15), 121 (100).
Anal. Calcd for C25H40O2 (372.58): C, 80.59; H, 10.82. Found: C,
85.60; H, 10.84.
1H NMR (200 MHz, CDCl3): = 7.07 (d, J = 8.0 Hz, 1 H), 6.75 (d,
J = 8.0 Hz, 1 H), 6.10–6.00 (m, 1 H), 5.23–5.11 (m, 3 H), 3.47 (d,
J = 5.5 Hz, 2 H), 2.58 (t, J = 7.8 Hz, 2 H); 1.88 (quar, J = 7.5 Hz, 2
H), 1.56 (quint, J = 7.5 Hz, 2 H), 1.48–1.29 (m, 30 H), 0.92 (t, J =
6.7 Hz, 3 H), 0.69 (t, J = 7.5 Hz, 3 H).
13C NMR (50.32 MHz, CDCl3): = 9.56, 14.01, 22.69, 27.89,
29.37, 29.52, 29.60, 29.66, 29.69, 29.72, 29.79, 30.85, 31.25, 31.93,
33.36, 33.66, 38.81, 116.44, 121.19, 122.85, 126.12, 132.53,
136.08, 139.77, 153.52.
6-n-Pentadecyl-4,5-dihydro-3H-benzo[b]oxepin-2-one (12)
Yield: 95%; white solid; mp 31–33 °C.
IR (neat): 3050, 2923, 2855, 1770, 1606, 1577 cm–1.
1H NMR (200 MHz, CDCl3): = 7.16 (t, J = 7.7 Hz, 1 H), 7.03 (d,
J = 7.7 Hz, 1 H), 6.93 (d, J = 7.7 Hz, 1 H), 2.84 (t, J = 7.1 Hz, 2 H),
2.63 (t, J = 7.5 Hz, 2 H), 2.45 (t, J = 7.1 Hz, 2 H), 2.14 (quint, J =
7.1 Hz, 2 H), 1.65–1.15 (m, 26 H), 0.87 (t, J = 6.5 Hz, 3 H).
13C NMR (50.32 MHz, CDCl3): = 14.09, 22.65, 23.32, 26.23,
29.32, 29.46, 29.53, 29.60, 29.63, 29.66, 31.08, 31.73, 31.89, 33.34,
117.04, 127.02, 127.29, 128.05, 141.81, 152.25, 171.78.
EIMS: m/z (%) = 414 (M+, 5), 386 (30), 385 (100).
Anal. Calcd for C28H48O (414.71): C, 83.99; H,12.15. Found: C,
83.99; H, 12.15.
EIMS: m/z (%) = 372 (24), 344 (4), 317 (2), 199 (6), 176 (93), 175
(12), 147 (21), 121 (100).
6-tert-Butyl-2-(1-methylallyl)-3-n-pentadecylphenol (9c)
Yield: 76%; white solid; mp 55–57 °C.
IR (nujol): 3533, 2956, 1649, 1612 cm–1.
Anal. Calcd for C25H40O2 (372.58): C, 80.59; H, 10.82. Found: C,
85.60; H, 10.84.
1H NMR (400 MHz, CDCl3): = 0.96 (t, J = 6.8 Hz, 3 H,CH3), 1.33
(s, 26 H, CH2), 1.44 [s, 9 H, C(CH3)3], 1.52 (d, J = 6.9Hz, 3 H, CH3),
2.62 (t, J = 7.5 Hz, 2 H, CH2), 3.94 (dq, J = 6.8, 4.4 Hz, 1 H, ArCH),
5.46 (dd, J = 10.4, 2.4 Hz, 1 H, =CH), 5.48 (dd, J = 17.2, 2.4 Hz, 1
H, =CH), 5.78 (br s, 1 H, OH, D2O exch.), 6.36 (ddd, J = 17.2, 10.4,
4.4 Hz, 1 H, =CH), 6.75 (d, J = 8.0 Hz, 1 H, Ar), 7.15 (d, J = 8.0 Hz,
1 H, Ar).
13C NMR (100.64 MHz, CDCl3): = 14.41, 16.29, 22.99, 29.68,
29.83, 29.91, 30.01, 32.09, 32.24, 34.56, 35.81, 116.03, 121.59,
125.20, 127.91, 135.72, 139.40, 142.79, 154.81.
9-tert-Butyl-6-n-pentadecyl-4,5-dihydro-3H-benzo[b]oxepin-2-
one (18a)
Yield: 90%; oil.
IR (neat): 3050, 2923, 2855, 1770, 1606, 1577 cm–1.
1H NMR (200 MHz, CDCl3): = 0.87 (t, J = 6.5 Hz, 3 H). 1.00–1.60
[m, 35 H, 26 H CH2, and 9 H C(CH3)3], 2.08 (quint, J = 7.0 Hz, 2
H), 2.39 (t, J = 7.0 Hz, 2 H), 2.58 (t, J = 7.5 Hz, 2 H), 2.82 (t, J =
7.0 Hz, 2 H), 6.97 (d, J = 8.1 Hz, 1 H), 7.17 (d, J = 8.1 Hz, 1 H).
13C NMR (50.32 MHz, CDCl3): = 13.10, 14.29, 20.99, 21.96,
22.73, 26.08, 28.28, 28.64, 28.99, 29.29, 29.53, 30.17, 30.91, 31.78,
32.10, 32.35, 33.20, 33.54, 36.08, 118.06, 123.44,125.57, 128.99,
134.74, 138.34, 137.43, 149.78, 170.96.
EIMS: m/z (%) = 414 (M+, 58), 399 (100), 357 (45), 345 (18).
Anal. Calcd for C29H50O (414.79): C, 83.99; H, 12.15. Found: C,
83.82; H, 11.79.
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Cardanol and Cardol Derivatives by Allylation and Regioselective Cyclocarbonylation Reactions
2755
EIMS: m/z (%) = 428 (M+, 25), 413 (100), 57(90), 121 (24), 135
6-n-Pentadecyl-4,5,11,12-tetrahydro-3H,10H-1,8-dioxaben-
(15), 161 (21), 177 (17), 203 (17).
zo(1,2,3,4)dicycloheptene-2,9-dione (22)
Yield: 90%; oil.
IR (neat): 2921, 2851, 1765, 1591, 1454, 1407 cm–1.
Anal. Calcd for C29H48O2 (428,69): C, 81.25; H, 11.29. Found: C,
81.25; H, 11.29.
1H NMR (200 MHz, CDCl3): = 0.87 (t, J = 6.5 Hz, 3 H, CH3),
1.05–1.67 (m, 26 H, CH2), 2.00–2.92 (m, 14 H), 6.83 (s, 1 H).
13C NMR (50.32 MHz, CDCl3): = 14.08, 22.65, 23.48, 23.97,
25.62, 26.06, 26.18, 26.28, 29.32, 29.42, 29.44, 29.51, 29.61, 29.65,
29.90, 31.03, 31.23, 31.36, 31.88, 31.99, 33.14, 118, 108, 133,
140.72, 150.72, 151.01, 171.18, 171.25.
9-(1,1-Dimethylpropyl)-6-n-pentadecyl-4,5-dihydro-3H-ben-
zo[b]oxepin-2-one (18b)
Yield: 90%; oil.
IR (neat): 3019, 2924, 2854, 1761, 1456 cm–1.
1H NMR (200 MHz, CDCl3): = 0.64 (t, J = 7.5 Hz, 3 H) , 0.87 (t,
J = 6.5 Hz, 3 H), 1.00–1.60 (m, 34 H), 2.08 (quint, J = 7.0 Hz, 2 H),
2.39 (t, J = 7.0 Hz, 2 H), 2.58 (t, J = 7.5 Hz, 2 H), 2.82 (t, J = 7.0
Hz, 2 H), 6.97 (d, J = 8.2 Hz, 1 H), 7.12 (d, J = 8.2 Hz, 1 H).
13C NMR (CDCl3): = 9.93, 14.54, 15.69, 23.11, 23.94, 26.35,
28.52, 29.78, 29.91, 29.99, 30.07, 30.08, 30.10, 31.50, 32.02, 32.33,
33.55, 34.22, 38.43, 120.0 , 126.87, 129.15, 136.39, 139.74, 151.10,
172.38
EIMS: m/z (%) = 456 (M+, 8), 260 (11), 205 (100).
Anal. Calcd for C27H44O2 (456.66): C, 76.27; H, 9.71. Found: C,
76.20; H, 10.00.
Acknowledgement
This work was supported by financial assistance from the Consiglio
Nazionale delle Ricerche (C.N.R.-Roma), the Ministero dell’Istru-
zione dell’Università e della Ricerca (M.I.U.R.-Roma), Consorzio
I.N.C.A. (Venezia), the Università degli Studi di Lecce and the Uni-
versità degli Studi di Urbino.
EIMS: m/z (%) = 442 (M+, 3) , 413 (100), 203 (82).
Anal. Calcd for C30H50O2 (442.72): C, 81.39; H, 11.38. Found: C,
80.90; H, 10.99.
1,3-Bisallyloxy-5-n-pentadecylbenzene (20)
Yield: 80%; white solid; mp 48–52 °C.
IR (neat): 2923, 2852, 1594, 1457 cm–1.
References
1H NMR (200 MHz, CDCl3): = 0.90 (t, J = 6.8 Hz, 3 H, CH3),
1.10–1.45 (m, 24 H), 1.48–1.67 (m, 2 H, CH2), 2.56 (t, J = 7.5 Hz,
2 H), 4.41–4.58 (m, 4 H, 2 OCH2), 5.15–5.42 (m, 4 H, =CH2), 5.90–
6.20 (m, 2 H, 2 CH=C), 6.22–6.38 (m, 3 H, Ar).
13C NMR (50.32 MHz, CDCl3): = 14.09, 14.11, 22.68, 29.31,
29.35, 29.51, 29.58, 29.68, 31.21, 31.89, 31.92, 36.26, 68.77, 98.98,
107.44, 117.58, 133.36, 145.33, 159.57.
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Amsterdam, 1996. (b) Tyman, J. H. P. Chem. Soc. Rev.
1979, 8, 499; and references cited therein.
(2) (a) Attanasi, O. A.; Buratti, S.; Filippone, P. Chim. Ind.
(Milano) 1996, 78, 693. (b) Attanasi, O. A. Chem. Today
1983, 11.
(3) (a) Attanasi, O. A.; Filippone, P.; Grossi, M. Ital. Patent
48737 A/85, 1985. (b) Attanasi, O. A.; Filippone, P.; Grossi,
M. Ital. Patent 47920 A/86, 1986. (c) Attanasi, O. A.;
Filippone, P.; Grossi, M. Phosph. Sulf. Relat. Elem. 1988,
35, 63. (d) Attanasi, O. A.; Filippone, P.; Balducci, S. Gazz.
Chim. Ital. 1991, 121, 487. (e) Attanasi, O. A.; Filippone, P.
Ital. Patent RM93A000605, 1993. (f) Attanasi, O. A.;
Buratti, S.; Filippone, P. Org. Prep. Proced. Int. 1995, 27,
645. (g) Attanasi, O. A.; Filippone, P. Ital. Patent
PS95A000021, 1995. (h) Coletta, M.; Filippone, P.;
Fiorucci, C.; Marini, S.; Mincione, E.; Neri, V.; Saladino, R.
J. Chem Soc., Perkin Trans. 1 2000, 581. (i) Filippone, P.;
Neri, V.; Mincione, E.; Saladino, R. Tetrahedron, in press.
(4) El-Ali, B.; Okuro, K.; Vasapollo, G.; Alper, H. J. Am. Chem.
Soc. 1996, 118, 4264.
(5) Troisi, L.; Vasapollo, G.; El-Ali, B.; Mele, G.; Florio, S.;
Capriati, V. Tetrahedron Lett. 1999, 40, 1771.
(6) Vasapollo, G.; Scarpa, A.; Mele, G.; Ronzini, L.; El-Ali, B.
Appl. Organomet. Chem. 2000, 14, 739.
(7) Amorati, R.; Pedulli, G. F.; Valgimigli, L.; Attanasi, O. A.;
Filippone, P.; Fiorucci, C.; Saladino, R. J. Chem. Soc.,
Perkin Trans. 2 2001, 2142.
EIMS: m/z (%) = 400 (M+, 12), 217, (18), 204 (100), 203 (63).
Anal. Calcd for C27H44O2 (400.64): C, 80.94; H, 11.07. Found: C,
80.60; H, 10.99.
2,4-Diallyl-5-n-pentadecylbenzene-1,3-diol (21)
Yield: 70%; oil.
IR (neat): 3543, 2921, 2851, 1506, 1465 cm–1.
1H NMR (200 MHz, CDCl3): = 0.91 (t, J = 6.7 Hz, 3 H, CH3),
1.02–1.46 (m, 24 H, CH2), 1.50–1.70 (m, 2 H, CH2), 2.58 (t, J = 7.9
Hz, 2 H), 3.39–3.60 (m, 4 H, ArCH2), 4.95–5.30 (m, 5 H, OH,
=CH2), 5.97–6.10 (m, 2 H, CH=C), 6.30 (s, 1 H, OH).
EIMS: m/z (%) = 400 (M+, 15), 217, (22), 204 (42), 203 (69),
201(25), 189 (100), 177 (57), 175 (73), 163 (94), 162 (88), 161 (84),
147 (31), 91 (15), 43 (44), 41 (27).
Anal. Calcd for C27H44O2 (400.64): C, 80.94; H, 11.07. Found: C,
80.60; H, 10.99.
(8) Shlyapnikov, Yu. A.; Kiryushkin, S. G.; Mar’in, A. P.
Antioxidative Stabilization of Polymers; Taylor & Francis:
London, 1996.
(9) Neri, C. Chim. Ind. (Milano) 1997, 79, 1223.
Synthesis 2002, No. 18, 2749–2755 ISSN 0039-7881 © Thieme Stuttgart · New York