Synthesis and Utility of α-Methoxy Phosphonates with a 1,3,2-Dioxaphosphorinane Ring

Article abstract of DOI:10.1055/s-2003-42395

Synthesis of several α-methoxy phosphonates with the phosphorus as a part of 1,3,2-dioxaphosphorinane ring by the simple reaction of (OCH ₂CMe₂CH₂O)PCl with acetals is described. Analogous methoxy phosphonates using (±) (C₂₀H ₁₂O₂)PCl were also synthesized using the same route. Utility of these phosphonates in the synthesis of vinyl ethers via the Horner-Wadsworth-Emmons [HWE] reaction is demonstrated.

Full text of DOI:10.1055/s-2003-42395

2368
PAPER
Synthesis and Utility of -Methoxy Phosphonates with a 1,3,2-Dioxaphospho-
rinane Ring
Methoxy
P
hosphonate
a
s
and
V
inyl
n
E
ther
s
ab Chakravarty, B. Srinivas, C. Muthiah, K. C. Kumara Swamy*
School of Chemistry, University of Hyderabad, Hyderabad - 500046, AP, India
Fax +91(40)23012460; E-mail: kckssc@uohyd.ernet.in.
Received 10 July 2003
Abstract: Synthesis of several -methoxy phosphonates with the
phosphorus as a part of 1,3,2-dioxaphosphorinane ring by the sim-
ple reaction of (OCH2CMe2CH2O)PCl with acetals is described.
Analogous methoxy phosphonates using ( ) (C20H12O2)PCl were
also synthesized using the same route. Utility of these phosphonates
in the synthesis of vinyl ethers via the Horner–Wadsworth–Em-
mons [HWE] reaction is demonstrated.
Key words: acetals, vinyl ethers, phosphorus, phosphonates, Hor-
ner–Wadsworth–Emmons reaction
Phosphonates of the type (RO)2P(O)CHR are valuable
precursors for C–C bond formation using the Horner–
Wadsworth–Emmons [HWE] reaction and hence consid-
erable efforts are directed towards the synthesis of new
derivatives or improving the existing methodology for the
known compounds.1 In our previous studies, we have
shown that the readily prepared, cheap and stable (to-
wards
oxidation
in
air)
chlorophosphite
(OCH2CMe2CH2O)PCl (1a) that features a saturated
1,3,2-dioxaphosphorinane is a convenient starting materi-
al for a variety of phosphonates, with or without -substi-
tution.2
Thus,
while
the
Pudovik
products
Scheme 1
(OCH2CMe2CH2O)P(O)CH(Ar)(OH) (2), obtained from
(OCH2CMe2CH2O)P(O)H (3, which itself is readily
formed by addition of water to 1a) lead to the -chloro/
bromo phosphonates (OCH2CMe2CH2O)P(O)CH(Ar)(X)
[4, X = Cl, Br] in high yields, the reaction of the P(III) de-
rivatives (OCH2CMe2CH2O)PX [1: X = Cl (a), NMe2 (b),
OMe (c), OSiMe3 (d)] with various aldehydes afforded
the phosphonates (OCH2CMe2CH2O)P(O)CH(Ar)(X)
[X = Cl (4), NMe2 (5), OMe (6), OSiMe3 (7)] in
variable yields. In a different approach, we have
utilized the facile Arbuzov rearrangement of
(OCH2CMe2CH2O)P[OCH(Ar)C(CN)=CH2)] (8; Ar =
Ph, C6H4-4-Me, ferrocenyl) formed in situ, using a Bay-
lis–Hillman methodology to obtain phosphonates of the
type [(OCH2CMe2CH2O)P(O)CH2C(CN)=CH(Ar)] (9).
These routes are shown in Scheme 1. In this paper, we re-
port a simple and convenient route to -methoxy phos-
phonates of type 6 using the reaction of 1a and the acetals
derived from aromatic aldehydes.3 Analogous phospho-
nates based on 1,1 -bi-2-naphthol are also synthesized.
Utility of these compounds in the synthesis of vinyl ethers
by HWE reaction will also be presented.
Treatment of 1a with the acetals ArCH(OMe)2 in anhy-
drous toluene affords the -methoxyphosphonates 6a–i in
good yields by the elimination of CH3Cl (Scheme 2). In
terms of reaction pathway, we believe that species of
types I–III (Figure 2) are involved; these have some com-
ponents similar to that reported in the reaction of acetals
with a mixture of PCl3 and P(OMe)3.4 The formation of
the methoxy derivative 1c [31P (C6D6): = 122.9 ppm;
Lit.5 (CDCl3): = 122.0 ppm] is readily seen by 31P NMR
when equimolar quantities of 1a and the dimethylacetal of
benzaldehyde are mixed together in C6D6 in a NMR tube.
Species II could not be clearly identified in the 1H NMR,
probably because the signals overlap with those due to
other protons or due to the instability of these species. Af-
ter 24 hours, only the peak due to the product 6a was seen
(Figure 1). Thus it is clear that this phosphonate is formed
quantitatively even at room temperature within a day.
SYNTHESIS 2003, No. 15, pp 2368–2372
x
x.
x
x
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2
0
0
3
Advanced online publication: 29.09.2003
DOI: 10.1055/s-2003-42395; Art ID: P06303SS
© Georg Thieme Verlag Stuttgart · New York

PAPER
Methoxy Phosphonates and Vinyl Ethers
2369
Reaction of the 1,1 -bi-2-naphthoxy compound
(C20H12O2)PCl (10) with acetals has also been performed
in an effort to see whether diastereomeric phosphonate
products can be distinguished (by NMR) or not. Of the
four phosphonates 11a–d (Figure 3) thus prepared by us-
ing the racemic binaphthol precursor ( ) (C20H12O2)PCl
(10), 11c and 11d showed two resonances in the 31P NMR
spectrum and even when the chiral phosphite (–)-10 was
used, the same two peaks were observed.
Scheme 2
Figure 3
The methoxy phosphonates 6a–i are air-stable solids that
can be handled conveniently. They undergo HWE reac-
tion with aldehydes very readily in the presence of the
cheap base NaH (Scheme 3) to lead to the vinyl ethers
12a–f and 13. Earlier, for analogous reactions, the more
expensive lithium diisopropylamide was used.4
Figure
1
31P NMR spectra (in C6D6) of: (a) pure
(OCH2CMe2CH2O)PCl (1a), (b) immediately after the addition of
acetal PhCH(OMe)2, c) 0.5 h after addition and (d) 24 h after addition.
Scheme 3
To summarize, since (i) the precursor 1a is cheap and very
readily prepared, and (ii) the -methoxy phosphonates
6a–i are formed in nearly quantitative yields (Figure 1)
under mild conditions, we believe that for the synthesis of
various vinyl ethers these phosphonates offer an elegant
choice as precursors, since the byproduct phosphate is wa-
ter-soluble.
Figure 2
Chemicals were procured from Aldrich or local manufacturers and
they were purified when required. Solvents were purified according
to standard procedures.6 The acetals except that of benzaldehyde
Synthesis 2003, No. 15, 2368–2372 © Thieme Stuttgart · New York

2370
M. Chakravarty et al.
PAPER
were prepared by using a literature method.7 1H, 13C and 31P NMR
spectra (operating at 200 MHz, 50 MHz, and 80.9 MHz respective-
ly) were recorded on a Bruker 200 MHz spectrometer with chemical
shifts (CDCl3) measured against TMS (1H, 13C) or 85% H3PO4. El-
emental analyses were carried out on a Perkin–Elmer 240C CHN
analyzer.
31P NMR: = 10.3.
Anal. Calcd for C14H21O5P: C, 56.00; H, 7.06. Found: C, 55.95; H,
7.12.
6e
Yield: 90%; mp 112–113 °C.
IR: 876, 1008, 1059, 1269, 1489, 2932 cm–1.
2-[Methoxy(3 -methyl-phenyl)methyl]-5,5-dimethyl-1,3,2-di-
oxaphosphorinan-2-one (6c); Typical Procedure
1H NMR: = 0.89, 1.20 (2 s, 6 H, 2 × CH3), 3.38 (s, 3 H, COCH3),
4.04–4.30 (m, 4 H, 2 × OCH2), 4.69 (d, 2JP–H = 15.8 Hz, 1 H, PCH),
7.35–7.56 (m, 4 H, ArH).
13C NMR: = 20.7, 21.9, 32.4 (d, 3JP–C = 8.3 Hz, CMe2), 58.7 (d,
3JP-C = 14.7 Hz, PCOCH3), 77.8, 78.4 (2 d, 2JP–C = 6.9 Hz, 7.0 Hz,
2-OCH2), 81.8 (d, 1JP–C = 162.4 Hz, PCH), 128.6, 129.0, 134.2.
Freshly distilled chlorophosphite (OCH2CMe2CH2O)PCl (1a) (3.03
g, 18.0 mmol)2b was added to freshly distilled [3-Me-
C6H4CH(OMe)2] (3.07 g, 18.5 mmol) in anhyd toluene under a an-
hyd N2 atmosphere. The reaction mixture was refluxed for two days.
Progress of the reaction was monitored by TLC and the product 6c
was isolated by column chromatography (EtOAc–hexane). Yield:
5.00 g (98%).
31P NMR: = 9.2.
Anal. Calcd for C13H18ClO4P: C, 51.24; H, 5.91. Found: C, 51.10;
H, 5.86.
All the other compounds 6a–b, 6d–i and 11a–d were prepared anal-
ogously using similar molar quantities.
6f
6a
Yield: 91%; mp 115–117 °C (lit.2c 120–122 °C).
Yield: 72%; mp 104–106 °C.
IR: 982, 1007, 1061, 1094, 1263, 1464, 1587, 2967 cm–1.
31P NMR: = 9.7 (lit.2c 9.8).
1H NMR: = 0.93, 1.22 (2 s, 6 H, 2 × CH3), 3.42 (s, 3 H, OCH3),
3.90–4.38 (m, 4 H, 2 × OCH2), 4.67 (d, 2JP–H = 16.6 Hz, 1 H, PCH),
7.30–7.60 (m, 3 H, ArH).
6b
Yield: 88%; mp 107–108 °C.
IR: 978, 1008, 1059, 1092, 1273, 1476, 1813, 2942 cm–1.
1H NMR: = 0.88, 1.18 (2 s, 6 H, 2 × CH3), 2.33 (s, 3 H, ArCH3),
3.37 (s, 3 H, OCH3), 3.90–4.30 (m, 4 H, 2 × OCH2), 4.68 (d,
2JP–H = 16.6 Hz, 1 H, PCH), 7.15–7.33 (m, 4 H, ArH).
13C NMR: = 20.7, 21.9, 32.6 (d, 3JP–C = 7.4 Hz, CMe2), 59.1 (d,
2
3JP–C = 14.4 Hz, POCH3), 77.8, 78.6 (2 d, JP–C = 7.5, 7.0 Hz, 2-
1
OCH2), 83.0 (d, JP–C = 162.3 Hz, P-CH), 127.1, 129.4, 130.5,
132.5, 132.8, 134.6.
31P NMR: = 8.4.
13C NMR: = 20.8, 21.2, 21.9, 32.4 (d, 3JP–C = 7.8 Hz, CMe2), 58.5
2
(d, 3JP–C = 15.3 Hz, PCOCH3), 77.5, 78.1 (2 d, JP–C = 6.9 Hz, 7.0
Anal. Calcd for C13H17O4Cl2P: C, 46.04; H, 5.02. Found C, 46.15,
H, 5.08.
1
Hz 2-OCH2), 82.1 (d, JP–C = 163.0 Hz, CH), 127.6, 127.7, 129.3,
131.0, 138.3.
31P NMR: = 10.2.
6g
Yield: 90%; mp 118–119 °C.
IR: 978, 1005, 1053, 1080, 1192, 1267, 1350, 1476, 2966 cm–1.
Anal. Calcd for C14H21O4P: C, 59.15; H, 7.39. Found: C, 59.13, H,
7.27.
1H NMR: = 0.90, 1.21 (2 s, 6 H, 2 × CH3), 3.40 (s, 3 H, OCH3),
4.05–4.40 (m, 4 H, 2 × OCH2), 4.67 (d, 2JP–H = 16.6 Hz, 1 H, PCH),
7.20–7.60 (m, 4 H, ArH).
6c
Yield: 98%; mp 102–104 °C.
IR: 980, 1005, 1053, 1082, 1269, 1368, 1480, 2967 cm–1.
13C NMR: = 20.8, 21.9, 32.5 (d, 3JP–C = 7.5 Hz, CMe2), 59.0 (d,
3JP–C = 14.5 Hz, PCOCH3), 77.8, 78.4 (2 d, 2JP–C = 9.7 Hz, 7.2 Hz,
1H NMR: = 0.90, 1.21 (2 s, 6 H, 2 × CH3), 2.37 (s, 3 H, ArCH3),
1
3.40 (s, 3 H, PCOCH3), 3.99–4.30 (m, 4 H, OCH2), 4.64 (d, 2JP–H
=
2-OCH2), 81.7 (d, JP–C = 162.3 Hz, PCH), 122.7, 126.5, 130.3,
131.6.
15.6 Hz, 1 H, PCH), 7.22–7.24 (2 br s, 4 H, ArH).
31P NMR: = 9.0.
13C NMR: = 20.7, 21.3, 21.9, 32.3 (d, 3JP–C = 7.3 Hz, CMe2), 58.6
(d, 3JP–C = 17.0 Hz, POCH3), 77.6, 78.2 (2 d, 2JP–C = 7.2 Hz, 7.3 Hz,
Anal. Calcd for C13H18BrO4P: C, 44.70; H, 5.16. Found: C, 44.52;
H, 5.05.
1
2-OCH2), 82.3 (d, JP–C = 162.5 Hz, PCH), 124.7, 124.8, 128.3,
129.2, 133.9, 138.0.
31P NMR: = 10.1.
6h
Yield: 89%; mp 134–136 °C.
IR: 1015, 1061, 1097, 1279, 1472, 2967 cm–1.
Anal. Calcd for C14H21O4P: C, 59.15; H, 7.39. Found: C, 59.22 H,
7.42.
1H NMR: = 0.83, 1.16 (2 s, 6 H, 2 × CH3), 3.43 (s, 3 H, OCH3),
4.01–4.20 (m, 4 H, 2 × OCH2), 5.50 (d, 2JP–H = 16.0 Hz, 1 H, PCH),
7.51–8.21 (m, 7 H, ArH).
13C NMR: = 20.8, 21.9, 32.4 (d, 3JP–C = 7.2 Hz, CMe2), 58.7 (d,
3JP–C = 14.5 Hz, PCOCH3), 77.5, 77.9 (2 d, 2JP–C = 7.3, 7.3 Hz, 2-
OCH2), 78.8 (d, 1JP–C = 135.8 Hz, PCH), 123.8, 125.2, 126.3, 130.2.
6d
Yield: 80%; mp 104–106 °C.
IR: 837, 1006, 1057, 1094, 1253, 1472, 1512, 1610, 2940 cm–1.
1H NMR: = 0.89, 1.19 (2 s, 6 H, 2 × CH3), 3.36 (s, 3 H, OCH3),
3.80 (s, 3 H, ArOCH3), 3.98–4.27 (m, 4 H, 2 × OCH2), 4.65 (d,
2JP–H = 15.6 Hz, 1 H, PCH), 6.92 and 7.37 (2 d, 3JH–H = 6.8 Hz, 4 H,
ArH).
31P NMR: = 9.7.
13C NMR: = 20.7, 21.8, 32.3 (d, 3JP–C = 7.4 Hz, CMe2), 55.2, 58.3
6i
(d, 3JP–C = 15.1 Hz, POCH3), 77.4, 77.9 (2 d, 2JP–C = 7.1 Hz, 7.3 Hz
Yield: 90%; mp 82–84 °C.
IR: 945, 979, 1008, 1055, 1086, 1265, 1477, 1579, 1647, 2970 cm–1.
1
2 OCH2), 81.6 (d, JP–C = 163.9 Hz, PCH), 114.0, 125.9, 129.1,
159.8.
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Methoxy Phosphonates and Vinyl Ethers
2371
1H NMR: = 0.96, 1.21 (2 s, 6 H, 2 CH3), 3.47 (s, 3 H, OCH3), 3.97–
4.43 (m, 5 H, 2 × OCH2, PCH), 6.25–6.31 [m, 1 H, PCH(OMe)CH],
6.65 (dd, 3JP–H = 4.6, 16.3 Hz, 1 H, CH=CHPh), 7.25–7.44 (m, 5 H,
Ar-H).
Anal. Calcd. for C28H20BrO4P: C, 63.29; H, 3.79. Found C, 63.35;
H, 3.81.
11d
Yield: 90%; mp > 240 °C.
IR: 966, 1223, 1271, 1327, 1348, 1464, 1520 (vs), 1591, 1610 cm–1.
13C NMR: = 20.8, 21.9, 32.5 (d, 3JP–C = 7.5 Hz, CMe2), 59.0 (d,
3JP–C = 14.5 Hz, PCOCH3), 77.8, 78.4 (2 d, 2JP–C = 9.7, 7.2 Hz, 2-
OCH2), 81.7 (d, 1JP–C = 162.3 Hz, PCH), 122.7, 126.5, 130.3, 131.6.
1H NMR: = 3.33 and 3.38 [1:3, 2 s, 3 H, CH(OCH3)], 4.71, 5.04
31P NMR: = 10.7.
(2 d, 2JP–H = 14.4, 17.9 Hz, 1 H, PCH), 7.23–8.47 (m, 16 H, ArH).
3
Anal. Calcd for C15H21O4P: C, 60.81; H, 7.09. Found C, 60.64, H,
7.21.
13C NMR: = 58.9 (d, JP-C = 15.0 Hz, PCOCH3), 77.5 (d, 1JP-C
=
160 3 Hz, PCH), 120.3, 120.9, 123.9, 125.9, 126.0, 126.9, 127.3,
128.9, 129.2, 129.3, 131.2, 131.5, 131.7, 131.9, 132.5, 140.2. The
signals of the other isomer are probably merged with those of the
major isomer.
Methoxy Phosphonates ( ) (C20H12O2)P(O) CH(OMe)(Ar) 11a–
d; General Procedure
PCl3 (3.0 mL, 34.0 mmol) was added to binapthol (2.00 g, 7.0
mmol) and the mixture refluxed for 2 d at 90 °C. Excess PCl3 was
removed under vacuum and the solid ( )(C20H12O2)PCl [10; 31P
(C6D6): = 177.9; lit.8 176.4] obtained was directly used for further
reactions.
31P NMR: = 25.2, 24.7.
Anal. Calcd. for C28H20NO6P: C, 67.60; H, 4.05; N, 2.82. Found C,
67.51; H, 4.09; N, 2.86.
MS (FAB): m/z = 497 [M]+, 498 [M + 1]+.
Freshly distilled acetal, PhCH(OMe)2 (0.43 g, 2.8 mmol) was added
to ( )(10) (1.00 g, 2.8 mmol) in anhyd toluene. This mixture was re-
fluxed at 120 °C for 2 d to give the -methoxyphosphonates. They
were obtained in a pure state by column chromatography (EtOAc–
hexane, 1:1).
Vinyl Ethers 12a–f and 13; Typical Procedure
The phosphonate 6a (0.6 g, 2.21 mmol) was dissolved in THF (10
mL) and slowly added to a suspension of NaH (0.12 g of 80% dis-
persion, 5.00 mmol) in THF (20 mL) at 0 °C (5 min); the mixture
was stirred at this temperature for 0.5 h. Then, 4-methoxybenzalde-
hyde (0.3 g, 2.20 mmol) in THF (10 mL) was added (5 min) and the
mixture heated under reflux for 15 h. Water (20 mL) was added and
the aq layer was extracted with Et2O (3 × 20 mL). The organic layer
was collected, dried (Na2SO4), filtered and solvent was removed
from the filtrate to give a residue that was purified by column chro-
matography (hexane) to obtain 12a (0.42 g, 80%) as a mixture of E
and Z isomers.
11a
Yield: 1.1 g (85%); mp > 240 °C (dec.).
IR: 964, 1223, 1271, 1462, 1507, 1589, 1620 (w) cm–1.
1H NMR: = 3.28 and 3.36 [5:1 ratio, 2 s, 3 H, CH(OCH3)], 4.61
2
and 4.88 (ratio 1:5, d each, JP–H = 13.1 and 15.8 Hz, 1 H, PCH),
7.19–8.20 (m, 17 H, ArH).
13C NMR: = 58.3 (d, 3JP–C = 15.2 Hz, PCOCH3), 80.5 (d, 1JP–C
=
In the preparation of 13, 2:1 molar ratio of the phosphonate to
159.7 Hz, PCH), 120.4, 121.4, 125.6, 125.7, 126.6, 127.2, 128.3,
128.6, 129.2, 130.9, 131.2, 131.5, 132.0, 132.8, 145.6, 148.9, 149.1,
151.8.
terephthalaldehyde was used.
12a
Yield: 80%, oil. Use of K2CO3/xylene in place of NaH/THF also
gave 1:1 mixture of isomers.
IR: 1510, 1606, 1635 cm–1.
1H NMR: = 3.68, 3.78, 3.84, 3.87 (4 s, 6 H, C=COCH3 and
ArOCH3, E/Z, 1:1), 5.85, 6.16 (2 s, 1 H, CH=C), 6.72 (d, 3JH–H = 8.7
Hz, one isomer), 6.96 (d, 3JH–H = 8.7 Hz, 2 H, ArH), 7.31–7.76 (m,
7 H, ArH).
13C NMR: = 55.2, 55.3, 55.5, 57.8 (COCH3, ArOCH3), 101.3,
112.6, 113.6, 126.4, 128.1, 128.3, 128.5, 128.8, 129.4, 130.0, 155.0,
156.5, 157.5, 159.4.
31P NMR: = 27.6.
Anal. Calcd for C28H21O4P: C, 74.33; H, 4.67. Found C, 74.28; H,
4.62.
11b
Yield: 65%; mp > 240 °C (dec.)
IR: 961, 1225, 1292, 1460, 1508, 1588, 1620 (w) cm–1.
1H NMR: = 2.28 (s, 3 H, ArCH3), 3.34 [s, 3 H, CH(OCH3)], 4.56
(d, 2JP–H = 13.2 Hz, 1 H, PCH), 7.12–8.18 (m, 16 H, ArH).
13C NMR: = 21.3, 57.9 (d, 3JP–C = 16.8 Hz, PCOCH3), 77.8 (d,
1JP–C = 162.9 Hz, PCH), 120.6, 121.3, 125.7, 126.7, 127.3,
128.5,128.7, 128.8, 129.4, 130.9, 131.2, 131.6, 131.9, 132.5, 139.1,
145.6, 148.9, 149.1.
Anal. Calcd for C16H16O2: C, 79.96; H, 6.72. Found: C, 80.05; H,
6.75.
12b
31P NMR: = 27.7.
Yield: 75% (mixture of two isomers); mp 70–72 °C.
IR: 1516, 1610, 1640 cm–1.
Anal. Calcd for C29H23O4P: C, 74.67; H, 4.97. Found C, 74.70; H,
4.90.
1H NMR: = 3.65, 3.85 (2 s, 3 H, COCH3, E/Z, 1:1), 5.85, 6.04 [2
s, 1 H, CH=C(OMe)], 6.95 (d, 3JH–H = 8.6 Hz, 2 H, ArH), 7.30–8.20
(m, 7 H, ArH).
13C NMR: = 55.6, 59.2 (COCH3), 103.0, 113.2, 123.5, 124.5,
127.0–131.5 (many lines), 157.2, 159.6.
11c
Yield: 85%; mp > 240 °C.
IR: 962, 1225, 1273, 1292, 1325, 1359, 1462, 1506, 1589, 1618
cm–1.
Anal. Calcd for C15H13O3N: C, 70.56; H, 5.14; N, 5.48. Found: C,
70.60; H, 5.30; N, 5.50.
1H NMR: = 3.29 and 3.41 [9:1, 2 s, 3 H, CH(OCH3)], 4.58, 4.95
(1:9, d each, 2JP–H = 12.6, 14.7 Hz, 1 H, PCH), 7.23–8.06 (m, 16 H,
ArH).
The compound was not very soluble to get a good 13C NMR.
31P NMR: = 27.8 and 27.6.
12c
Yield: 90%; mp 64–66 °C (lit.4 mp 62–63 °C).
IR: 1425, 1450, 1512, 1601, 1703 cm–1.
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M. Chakravarty et al.
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1H NMR: = 3.72 (s, 3 H, COCH3), 3.82 (s, 3 H, ArOCH3), 5.94 [s,
1H NMR: = 3.66, 3.72,3.81, 3.86 [4 s, 6 H, C=C(OCH3)], 5.81,
5.90, 6.08, 6.20 (4 s, 2 H, CH=C), 6.79–7.79 (m, 14 H, ArH).
13C NMR: = 55.5, 55.6, 57.9, 58.0 (COCH3), 101.6, 101.8, 112.9,
126.6 (CH=C), 128.2, 128.3, 128.5, 128.6, 128.7, 128.9, 129.4,
129.0, 129.4, 133.0, 133.9, 134.3, 135.3, 136.6, 155.8, 156.2, 156.9,
157.4 (COMe).
3
1 H, CH=C(COMe)], 6.64 (d, JH–H = 16.1 Hz, 1 H, CH=CHPh),
6.84 (d, 3JH–H = 15.5 Hz, 1 H, CH=CHPh), 6.86–7.65 (m, 9 H, ArH).
13C NMR: = 47.6 (COCH3), 55.3 (ArOCH3), 114.3, 128.3, 128.9,
130.5, 142.5, 157.5, 161.4.
Anal. Calcd for C18H18O2: C, 81.20; H, 6.77. Found: C, 81.02; H,
6.52.
Anal. Calcd for C24H22O2: C, 84.17; H, 6.47. Found: C, 84.22; H,
6.42.
12d
Yield: 88% (mixture of two isomers); mp 66–70 °C.
IR: 1338, 1446, 1502, 1579 cm–1.
Acknowledgment
We acknowledge financial support from the Council of Scientific
and Industrial Research (CSIR) and Department of Science and
Technology (DST), New Delhi for financial support. MC is thank-
ful to CSIR for a fellowship. We also thank University Grants Com-
mission (UGC), New Delhi for equipment under the UPE
programme.
1H NMR: = 3.78 (s, 3 H, COCH3), 3.86 (s, 3 H, COCH3), 5.89,
6.02 [2 s, 1 H, (Ar)CH=C(COMe)], 6.70 (d, 3JH–H = 15.8 Hz, 1 H,
CH=CHPh), 6.92 (d, 3JH–H = 15.8 Hz, 1 H, CH=CHPh), 6.97–8.22
(m, 9 H, ArH).
13C NMR: = 55.3, 59.0 (COCH3), 102.5, 114.3, 119.9, 123.7,
123.8, 124.0, 127.0–132.4 (many lines), 133.2, 136.4, 144.5, 157.0,
159.5.
References
Anal. Calcd for C17H15NO3: C, 72.57; H, 5.38; N, 4.97. Found: C,
72.67; H, 5.40; N, 5.00.
(1) Selected references: (a) Shen, Y.; Ni, J.; Li, P.; Sun, J. J.
Chem. Soc., Perkin Trans. 1 1999, 509. (b) Iorga, B.;
Eymery, F.; Savignac, P. Synthesis 2000, 576. (c) Tago, K.;
Kogen, H. Org. Lett. 2000, 2, 1975. (d) Sun, S.; Turchi, I. J.;
Xu, D.; Murray, W. V. J. Org. Chem. 2000, 65, 2555.
(e) Vaes, L.; Rein, T. Org. Lett. 2000, 2, 2611. (f) Reiser,
U.; Jauch, J. Synlett 2001, 90. (g) Crist, R. M.; Reddy, P. V.;
Borhan, B. Tetrahedron Lett. 2001, 42, 619. (h) Kawasaki,
T.; Nonaka, Y.; Watanabe, K.; Ogawa, A.; Higuchi, K.;
Terashima, R.; Masuda, K.; Sakamoto, M. J. Org. Chem.
2001, 66, 1200. (i) Gelman, D.; Jiang, L.; Buchwald, S. L.
Org. Lett. 2003, 5, 2315. (j) Pamies, O.; Backyall, J.-E. J.
Org. Chem. 2003, 68, 4815.
12e
Yield: 50%; mp 62–64 °C.
IR: 1001, 1067, 1240, 1273, 1314, 1599 cm–1.
1H NMR: = 2.42 (s, 3 H, Ar-CH3.), 3.64 [s, 3 H, C=C(OCH3)],
4.16 (s, 5 H, ferrocenyl-H, unsubstituted ring), 4.28, 4.67 (2 s, 4 H,
ferrocenyl-H, substituted ring), 5.99 [s, 1 H, C(OMe)=CH], 7.33–
7.40 (m, 4 H, ArH).
13C NMR: = 21.5 (Ar-CH3), 57.8 [C=C(OCH3)], 68.7, 69.0, 69.3,
(ferrocenyl-C), 80.8 [C(ferrocenyl)CH=C(OMe)-], 111.0, 122.9,
126.4, 128.4, 136.3, 138.0, 153.9 [CH=C(OMe)].
(2) (a) Kumaraswamy, S.; Selvi, R. S.; Kumara Swamy, K. C.
Synthesis 1997, 207. (b) Muthiah, C.; Praveen Kumar, K.;
Aruna Mani, C.; Kumara Swamy, K. C. J. Org. Chem. 2000,
65, 3733. (c) Praveen Kumar, K.; Muthiah, C.;
Kumarswamy, S.; Kumara Swamy, K. C. Tetrahedron Lett.
2001, 42, 3215. (d) Senthil Kumar, K.; Kumara Swamy, K.
C. J. Organomet. Chem. 2001, 637-639, 616. (e) Muthiah,
C.; Senthil Kumar, K.; Vittal, J. J.; Kumara Swamy, K. C.
Synlett 2002, 1787.
(3) Maleki, M.; Miller, A.; Lever, O. W. Jr. Tetrahedron Lett.
1981, 22, 365.
(4) Fettes, K.; McQuire, L.; Murray, A. W. J. Chem. Soc.,
Perkin 1 1995, 2123.
Anal. Calcd for C20H20FeO: C, 72.30; H, 6.07. Found: C, 72.18; H,
6.06.
12f
Yield: 80% (mixture of isomers); mp 130–132 °C.
IR: 887, 1024, 1103, 1238, 1339, 1381, 1468, 1622 cm–1.
1H NMR: = 3.15, 4.12 [2 s, 3 H, C=C(OCH3), mixture of two iso-
mers, ratio 1:2], 6.39–8.23 [m, 13 H, C(OMe)=CH, anthracenyl-H
merged together).
13C NMR: = 56.0, 59.1, (COCH3), 97.6, 104.8 [CH=C(OMe)],
125.2, 125.3, 125.5, 125.6, 125.8, 125.9, 126.3, 126.5, 126.8, 127.0,
128.2, 128.8, 129.4, 129.5, 129.6, 130.1, 130.2, 130.4, 131.4, 132.9,
137.1, 155.3, 155.7.
(5) Denney, D. Z.; Denney, D. B. J. Am. Chem. Soc. 1966, 88,
1830.
(6) Perrin, D. D.; Armarego, W. L. F.; Perrin, D. R. Purification
of Laboratory Chemicals; Pergamon: Oxford UK, 1986.
(7) Meskens, F. A. Synthesis 1981, 501.
Anal. Calcd for C23H16Cl2O: C, 72.83; H, 4.25. Found: C, 72.75; H,
4.22.
13
(8) Scherer, J.; Huttner, G.; Büchner, M.; Bakos, J. J.
Oganomet. Chem. 1996, 520, 45.
Yield: 63%; mp 120–122 °C.
IR: 694, 766, 1066, 1448, 1632, 1682, 2932 cm–1.
Synthesis 2003, No. 15, 2368–2372 © Thieme Stuttgart · New York