Chlorophosphonates: Inexpensive precursors for stereodefined chloro- substituted olefins and unsymmetrical disubstituted acetylenes

Article abstract of DOI:10.1021/jo991946y

New chlorophosphonates bearing a 1,3,2-dioxaphosphorinane ring which are useful for the stereospecific synthesis of 5-chlorofurfuryl substituted olefins and chloro-substituted dienes have been obtained by an easy, inexpensive route. The utility of some of these in the synthesis of ferrocenyl- and anthracenyl-substituted unsymmetrical acetylenes has been explored. The structures of the phosphonates (OCH₂CMe₂CH₂O)P(O)CH₂(C₄H₂ClO) (4) and (OCH₂CMe₂CH₂O)P(O)(CH=CHCH(Cl)Ph (7) have been determined; in addition, the stereochemistry of (5-chlorofurfuryl)CH=CH(4-ClC₆H₄) (13b) and 2,4- Cl₂C₆H₃-CH=CH-CH=C(Ph)Cl (14a) is unambiguously proved by the X-ray structure determination.

Full text of DOI:10.1021/jo991946y

J . Org. Chem. 2000, 65, 3733-3737
3733
Ch lor op h osp h on a tes: In exp en sive P r ecu r sor s for Ster eod efin ed
Ch lor o-Su bstitu ted Olefin s a n d Un sym m etr ica l Disu bstitu ted
Acetylen es
C. Muthiah, K. Praveen Kumar, C. Aruna Mani, and K. C. Kumara Swamy*
School of Chemistry, University of Hyderabad, Hyderabad-500046, A. P., India
Received December 20, 1999
New chlorophosphonates bearing a 1,3,2-dioxaphosphorinane ring which are useful for the
stereospecific synthesis of 5-chlorofurfuryl substituted olefins and chloro-substituted dienes have
been obtained by an easy, inexpensive route. The utility of some of these in the synthesis of
ferrocenyl- and anthracenyl-substituted unsymmetrical acetylenes has been explored. The struc-
tures of the phosphonates (OCH2CMe2CH2O)P(O)CH2(C4H2ClO) (4) and (OCH2CMe2CH2O)P(O)-
(CHdCHCH(Cl)Ph (7) have been determined; in addition, the stereochemistry of (5-chlorofurfuryl)-
CHdCH(4-ClC6H4) (13b) and 2,4-Cl2C6H3-CHdCH-CHdC(Ph)Cl (14a ) is unambiguously proved
by the X-ray structure determination.
In tr od u ction
us before. These results along with the stereospecific
synthesis of 5-chlorofurfuryl substituted olefins and
trisubstituted dienes are described herein.
Despite the fact that phosphonates are now well
established as having enormous synthetic utility, new
reagents that will be useful for specific synthetic goals
are still being discovered.1 We have been interested in
developing new phosphonate reagents and have reported
the high-yield synthesis of a large number of R-bromo
and R-chloro phosphonates 22,3 derived from the readily
prepared cyclic phosphite (OCH2CMe2CH2O)P(O)H (1).
The ease of synthesis and purification coupled with the
use of cheap chemicals prompted us to explore their
utility and indeed we have been able to achieve an easy
access to trisubstituted vinyl chlorides and improved
synthesis of chloro and bromostilbenes.4,5 In the present
study we have used the R-hydroxyphosphonates obtained
from the Pudovik reaction6 of 1 with furfuraldehyde and
cinnamaldehyde. Chlorination of the R-hydroxyphospho-
nates occurs in a fashion different from that reported by
Another aspect of interest was the inevitable corollary
that the phosphonates 2a can be valuable synthons for
unsymmetrical disubstituted acetylenes by the elimina-
tion of HCl from the products of the Horner-Wad-
sworth-Emmons reaction. The present study offers a
convenient route to acetylenes bearing ferrocenyl/anthra-
cenyl residues;7,8 the latter products, we believe, will be
interesting electrochemically9 and photochemically.10 It
is also of interest to note that use of a cyclic phosphonate,
in particular one with a six-membered ring, may avoid
side reactions, and hence, higher yields of the expected
products may be obtained.11
* To whom correspondence should be addressed. Fax: +91-40-
3010120. E-mail: kckssc@uohyd.ernet.in.
(1) Selected references: (a) Tsai, H.-J ., Thenappan, A.; Burton, D
J . J . Org. Chem. 1994, 59, 7085. (b) Tanaka, K., Otsubo, K.; Fuji, K.
Tetrahedron Lett. 1996, 37, 3735. (c) Kojima, S.; Takagi, R.; Akiba,
K.-y. J . Am. Chem. Soc. 1997, 119, 5970. (d) Shen, Y.; Ni, J . J . Org.
Chem. 1997, 62, 7260. (e) Palacios, F., Alonso, C.; Rubiales, G. J . Org.
Chem. 1997, 62, 1146. (f) Ando, K. J . Org. Chem. 1997, 62, 1934. (g)
Sanu, S.; Yokoyama, K.; Fukushima, M.; Yagi, T.; Nagao, Y. J . Chem.
Soc., Chem. Commun. 1997, 559. (h) Arai, S.; Hamaguchi, S.; Shioiri,
T. Tetrahedron Lett. 1998, 39, 2997. (i) Arai, T.; Sasai, H.; Yamaguchi,
K., Shibasaki, M. J . Am. Chem. Soc. 1998, 120, 441. (j) Davis, A. A.;
Rose´n, J . J .; Kiddle, J . J . Tetrahedron Lett. 1998, 39, 6263. (k) Takacs,
J . M.; J aber, M. R.; Clement, F.; Walters, C. J . Org. Chem. 1998, 63,
6757. (l) Tullis, J . S.; Vares, L.; Kann, N.; Norrby, P.-Ola; Rein, T. J .
Org. Chem. 1998, 63, 8284. (m) Shen, Y.; Ni, J .; Li, P.; Sun, J . J . Chem.
Soc., Perkin Trans. 1 1999, 509.
(7) Selected references on the synthesis of disubstituted acety-
lenes: (a) Zimmer, H.; Bercz, P. J .; Maltenieks, O. J .; Moore, M. W. J .
Am. Chem. Soc. 1965, 87, 2777. (b) Zimmer, H.; Hickey, K. R.;
Schumacher, R. J . Chimia 1974, 28, 656. (c) Glascoyne, J . M.; Mitchell,
P. J .; Philips, L.; J . Chem. Soc., Perkin Trans. 2 1977, 1051. (d)
Ishihara, T.; Mackawe, T.; Ando, T. Tetrahedron Lett. 1984, 25, 1377.
(e) Gallagher, M. J .; Noerdin, H. Aust. J . Chem. 1985, 38, 997. (f) Lee,
J . W.; Kim, T. H.; Oh, D. Y. Synth. Commun. 1989, 19, 2633. (g) Kondo,
K.; Ohnishi, N.; Takemoto, K.; Yoshida, H.; Yoshida, K. J . Org. Chem.
1992, 57, 1622. (h) Kondo, K.; Fujitani, T.; Ohnishi, N.; J . Mater. Chem.
1997, 7, 429. (i) J ohn, J . A., Tour, J . M. Tetrahedron 1997, 53, 15515.
(j) Mouries, V., Waschbusch, R.; Carran, J . Savignac, P. Synthesis 1998,
271. (k) Youngs, W. J .; Tessier, C. A.; Bradshaw, J . D. Chem. Rev. 1999,
99, 3153. (l) Pschirer, N. G.; Fu, W.; Adams, R. D.; Bunz, U. H. F. J .
Chem. Soc., Chem. Commun. 2000, 87. In c, e, g, and h, the route (a)
of Zimmer is used.
(2) Kumaraswamy, S.; Selvi, R. S.; Kumara Swamy, K. C. Synthesis
1997, 207.
(3) For other routes to R-monohalogenophosphonates, see: (a) Green,
D.; Elgendy, S.; Patel, G.; Baban, J . A.; Skordalakes, E.; Husman, W.;
Kakkar, V. V.; Deadman, J . Tetrahedron 1996, 52, 10215. (b) Iorga,
B.; Eymery, F.; Savignac, P. Tetrahedron 1999, 55, 2671.
(4) Kumaraswamy, S.; Kumara Swamy, K. C. Tetrahedron Lett.
1997, 38, 2183.
(5) Muthiah, C.; Praveen Kumar, K.; Kumaraswamy, S.; Kumara
Swamy, K. C. Tetrahedron 1998, 54, 14315.
(6) (a) Pudovik, A. N.; Konovalova, I. V. Synthesis 1979, 81. (b)
Engel, R. In Synthesis of Phosphorus-Carbon Bonds; CRC Press: Boca
Raton, FL, 1988; pp 101-136.
(8) Two reports pertaining to the synthesis of anthracenyl substi-
tuted acetylenes include: (a) Becker, H.-D.; Andersson, K. J . Org.
Chem. 1983, 48, 4542. (b) Inouye, M.; Konishi, T.; Isagawa, K. J . Am.
Chem. Soc. 1993, 115, 8091.
(9) Deeming, A. J . In Comprehensive Organometallic Chemistry;
Wilkinson, G., Stone, F. G. A., Abel, E. W., Eds.; Pergamon: Oxford,
England, 1982; Vol. 4, p 480.
(10) Klessinger, M.; Michl, J . Excited States and Photochemistry of
Organic Molecules; VCH: New York, 1995; pp 411 and 418.
(11) (a) Breuer, E.; Bannett, D. M. Tetrahedron 1978, 34, 997. (b)
Larsen, R. O.; Aksnes, G. Phosphorus Sulfur 1983, 16, 339.
10.1021/jo991946y CCC: $19.00 © 2000 American Chemical Society
Published on Web 05/16/2000

3734 J . Org. Chem., Vol. 65, No. 12, 2000
Muthiah et al.
F igu r e 1. ORTEP drawing of compound 4‚H2O; the solvent
molecule is not shown. Selected distances (Å) and angles
(deg): P-O(3) 1.457(4), P-O(1) 1.572(3), P-O(2) 1.577(3),
P-C(6) 1.801(4); O(3)-P-O(1) 112.0(2), O(3)-P-O(2)
112.3(2), O(1)-P-O(2) 105.02(16), O(3)-P-C(6) 113.9(2),
O(1)-P-C(6) 106.25(18), O(2)-P-C(6) 106.7(2).
F igu r e 2. ORTEP drawing of 7. Selected distances (Å) and
angles (deg): P-O(3) 1.445(4), P-O(1) 1.558(4), P-O(2)
1.577(4), P-C(6) 1.774(5), C(8)-C(7) 1.491(7), C(7)-C(6) 1.312-
(7); O(3)-P-O(1) 111.8(2), O(3)-P-O(2) 112.6(3), O(1)-P-
O(2) 104.9(2), O(3)-P-C(6) 114.0(3), O(1)-P-C(6) 106.5(2),
O(2)-P-C(6) 106.5(2), C(1)-O(1)-P 121.7(3), C(3)-O(2)-P
120.5(3)°.
Sch em e 1
Sch em e 3
Sch em e 4
Sch em e 2
Resu lts a n d Discu ssion
Syn th esis of P h osp h on a tes. The R-hydroxy furfuryl
phosphonate 3 is readily obtained by reacting the phos-
phite 1 with furfuraldehyde; treatment of 3 with thionyl
chloride afforded the 5-chlorofurfuryl phosphonate 4
(Scheme 1). The identity of 4 was proved by NMR spec-
troscopy, elemental analysis, as well as X-ray structure
determination (Figure 1). Compound 4 contains a PCH2
moiety instead of the PCH(Cl) moiety present in the
normal chlorinated derivatives (cf. 2a ). A possible path-
way for the formation of 4 is given in Scheme 2;
aromatization appears to be the driving force in the
conversion of the intermediate II to 4. We also attempted
bromination of 3 with thionyl bromide, but here a large
number of products that included (a) those with cleavage
of furfuryl ring (1H NMR), (b) phosphate esters [31P NMR
δ(P) -13.5], and (c) phosphonates [31P NMR: δ(P) 8.0]
were formed.
X-ray structure of 7 (Figure 2) unequivocally established
its identity.
The other phosphonates 9-12 used in this study are
the normal chlorination products of the corresponding
R-hydroxy phosphonates.
The R-hydroxy phosphonates 5 and 6 derived from the
reaction of 1 with cinnamaldehyde or crotonaldehyde
undergo allylic chlorination to afford the γ-chloro phos-
phonates 7 and 8 (Scheme 3). The 13C NMR spectra of 7
and 8 show a characteristic doublet at δ 117.2 [1J (P-C)
186.0 Hz] and 116.1 [1J (P-C) 186.5 Hz], respectively. The
Olefin a n d Acetylen e Syn th esis. Reaction of the
5-chlorofurfuryl phosphonate 4 with aromatic aldehydes
under mild conditions gives remarkably high (isolated)
yields of the E-olefin exclusively (Scheme 4); the stereo-
chemistry at the double bond was confirmed by deter-

Chlorophosphonates
J . Org. Chem., Vol. 65, No. 12, 2000 3735
Sch em e 5
Sch em e 7
Sch em e 6
mining the X-ray structure of 13b (see the Experimental
Section). Although phosphonate carbanions are known
to furnish a great preponderance of the trans (E) olefins,12
the results obtained here contrast with that obtained
using R-chlorophosphonates (OCH2CMe2CH2O)P(O)(CH-
Cl(Ar)) [Ar ) Ph, 4-MeC6H4 etc.] where both E and Z
isomers were obtained in comparable quantities.4,5 Thus,
it is likely that the stereospecificity is imparted by the
furfuryl oxygen, which could participate in the transition
state as shown in structure III.11-13
Sch em e 8
stituted acetylenes are also known.7-8,15-16 For the syn-
thesis of bis(aryl) acetylenes, the R-chlorophosphonates
used in this work are comparable to those used by
Zimmer.7a Compound 16a has been previously prepared
in good yields from benzyltriphenylphosphonium bromide
using a Wittig reaction, bromination, and double-elimi-
nation route.8b However, starting from the phosphonate
reagent, ours is a single-step procedure giving similar
yields and is cheaper in our assessment. The transition
metal mediated coupling between an aryl halide and a
terminal acetylene is also useful, but would require
synthesis of the latter in many cases.7i,k,l,8b
Compound 7 can also be utilized to prepare enynes
(Scheme 8); here, isomeric products are possible. Whereas
in the case of 17 both E and Z isomers were obtained
(the Z isomer is obtained in a pure state), for 18 only the
E isomer was isolated.
The reaction of phosphonate 7 with aromatic aldehydes
using K2CO3/xylene proceeds smoothly (Scheme 5) to give
high yields of the chloro-substituted dienes and only the
(E,Z) isomer is obtained; the stereochemistry was con-
firmed in the case of 14a by using X-ray crystallography.
Formation of the (E,Z) dienes 14 from 7 must have
occurred via the carbanion IV (Scheme 6) since in a blank
reaction of 7 with K2CO3/xylene without the aldehyde we
were able to isolate the phosphonate 7a , which has a
PCH2 entity. The stereospecificity observed here may be
contrasted with that reported by Murray and co-workers
in the reaction of R-methoxy allylphosphonates with
aldehydes and ketones using LDA as the base to yield
isomeric mixtures of dienes.14
In summary, we have developed new chlorophospho-
nates that have high potential for use in stereospecific
synthesis of chloro-substituted olefins and dienes. Utility
of these phosphonates in the synthesis of unsymmetrical
acetylenes bearing ferrocenyl and anthracenyl substitu-
ents is demonstrated.
Synthesis of acetylenes 15 and 16 is straightforward
(Scheme 7). Some other routes to unsymmetrical disub-
(12) (a) Kelly, S. E. In Comprehensive Organic Synthesis; Trost, B.
M., Ed. in Chief; Fleming, I., Deputy Ed.-in-Chief; Schreiber, S. L.,
Volume Ed.; Pergamon: Oxford, 1991; Vol. 1, p 762. (b) Ando, K. J .
Org. Chem. 1999, 64, 6815 (theoretical study).
(13) Patois, C.; Ricard, L.; Savignac, P. J . Chem. Soc., Perkin Trans.
1 1990, 1577 (for phosphoryl oxygen coordination).
(15) Ben-Efrain, D. A. In The Chemistry of Carbon-Carbon Triple
Bond; Patai, S., Ed.; J ohn Wiley and Sons: Bristol, Great Britain, 1978;
Part 2, pp 755-812.
(16) Watts, W. E. In Comprehensive Organometallic Chemistry;
Wilkinson, G., Stone, F. G. A., Abel, E. W., Eds.; Pergamon: Oxford,
1982; Vol. 8, pp 1014-1070.
(14) Fettes, K.; McQuire, L.; Murray, A. W. J . Chem. Soc., Perkin
Trans. 1 1995, 2123.

3736 J . Org. Chem., Vol. 65, No. 12, 2000
Muthiah et al.
21.0, 21.8, 32.6, 51.0 (d, J ) 155.0 Hz), 78.2 122.7, 125.3, 126.0,
127.0, 128.2, 128.3, 129.0, 130.0, 133.8; 31P NMR δ 8.5. Anal.
Calcd for C16H18ClO3P: C, 59.18; H, 5.60. Found: C, 59.12;
H, 5.49.
Exp er im en ta l Section
Compound 1 [δ(P) 2.3] was prepared in 98% yield by adding
water dropwise (3.47 g, 0.19 mol) to (OCH2CMe2CH2O)PCl [bp
78-79 °C/20 mm17] (32.5 g, 0.19 mol) cooled in ice and stirring
the contents for 12 h at room temperature inside an efficient
hood; it was dried in a vacuum (0.6 mm) for 2 h (to remove
traces of water, if any) and used as such for further reactions.
It can also be distilled in a vacuum (bp 93-94 °C/ 0.05 mm17).
An alternative procedure for 1 is also available.18 The R-hy-
droxyphosphonates 3, 5, and 6 were prepared by a procedure
described by us before.2
3: yield 96% (using 2.1 g, 14 mmol of 1); mp 104-106 °C;
IR (cm-1) 3300 (br, ν(OH)); 1H NMR δ 0.92, 1.20 (2 s, 6H),
3.90-4.30 (m, 4H), 5.22 (d, J ) 20.0 Hz, 1H), 6.35 (m, 1H),
6.50 (m, 1H), 7.50 (s, 1H); 13C NMR δ 20.8, 21.9, 32.5, 65.6 (d,
J ) 155.4 Hz), 77.6, 109.5, 109.6, 110.8, 142.9, 149.7; 31P NMR
δ 10.9. Anal. Calcd for C10H15O5P: C, 48.77; H, 6.15. Found:
C, 48.65; H, 6.06.
5: yield 80% (using 2.1 g, 14 mmol of 1); mp 141-142 °C;
IR (cm-1) 3154 (br, ν(OH)); 1H NMR δ 0.93, 1.14 (2 s, 6H),
3.90-4.10 (m, 2H), 4.20-4.35 (m, 2H), 4.87 (dd, J ) 6.0, 16.0
Hz, 1H), 6.35 (ddd, J ) 5.0, 6.0, 18.0 Hz, 1H), 6.80 (dd, J )
5.0, 18.0 Hz, 1H), 7.20-7.50 (m, 5H); 13C NMR δ 20.0, 21.8,
32.5 (d, J ) 7.5 Hz), 70.6 (d, J ) 160.0 Hz) 77.4 (J ≈ 5.0 Hz),
123.8, 126.7, 127.9, 128.5, 132.6 (J ) 2.5 Hz), 136.3; 31P NMR
δ 14.0. Anal. Calcd for C14H19O4P: C, 59.56; H, 6.79. Found:
C, 59.45; H, 6.68.
(a ) Rea r r a n gem en t of 7 to 7a . Compound 7 (0.6 g, 2.0
mmol) was heated with K2CO3 (0.5 g) in xylene (30 mL) at 80
°C for 20 h. To the residue after removal of xylene was added
ether, and the contents were washed with water. The ether
portion was dried (Na2SO4) and the solvent removed. The
residue was essentially 7a (liquid) [NMR, >95%]. Attempted
purification by column chromatography (for elemental analy-
sis) was not successful: 1H NMR δ 1.03, 1.06 (2 s, 6H), 3.10
(dd, J ) 7.8, 22.5 Hz, 2H), 3.88 (dd, 2H), 4.17 (dd, 2H), 6.19
(td f qrt, 1H), 7.20-7.60 (m, 5H); 13C NMR δ 21.4, 26.7 (d, J
) 136.5 Hz), 32.5 (d, J ) 4.5 Hz), 75.5, (d, J ) 7.0 Hz), 115.9
(d, J ) 11.0 Hz), 126.5, 128.4, 129.0, 137.3; 31P NMR δ 20.9;
MS 265 [M - Cl]+.
(b) Rea ction of 3 w ith SOBr 2. Compound 3 (0.5 g, 2 mmol)
in dichloromethane (10 mL) was stirred with an excess of
SOBr2 (0.5 mL, 1.3 g, 6.2 mmol) for 1 d at 25 °C. More
dichloromethane (10 mL) was added, the solution was washed
with water, and the organic layer was dried (Na2SO4). The
solvent was evaporated to get a solid. It was dissolved in
dichloromethane/heptane mixture, when a solid (A; 0 05 g)
precipitated. A: mp 94-96 °C; 1H NMR δ 0.92, 1.39 (2 s, 6H),
4.10 (dd, J ) 10.7, 16.7 Hz, 2H), 4.60 (d, J ) 10.7 Hz, 2H),
6.64 (d, J ≈ 3.8 Hz, 1H), 7.77 (s, 1H), 8.20 (d, J ≈ 3.8 Hz, 1H);
31P NMR δ -13.9 [The δ (P) value clearly suggests that the
compound is a phosphate ester19]; MS 244 [no Br isotopic
pattern]. The sample was unstable in CDCl3 solution, and
hence, a satisfactory 13C NMR spectrum could not be recorded.
The mother liquor showed a large number of peaks in the 31P
NMR [-14.2, -13.8, -13.3, (phosphate region); -6.1, -4.5,
-4.0, -1.7, 8.0, 12.8]. A small amount of a phosphonate
product [1H NMR δ 1.02, 1.10 (2 s, 6H), 3.80-4.10 (m, 4H),
6.32 (d, J ) 14.4 Hz, ∼1H), 7.30-8.00 (m, ca. 5H); 31P NMR δ
8.0] was also isolated, but was not analyzed further because
of the very low yield.
6: yield 20% [using 2.1 g (14 mmol) of 1; a longer reaction
time of 3 d and column chromatographic separation from the
starting material was required to get a pure product]; mp 92-
1
94 °C; IR (cm-1) 3412 (br, ν(OH)); H NMR δ 0.98, 1.14 (2 s,
6H), 1.74 (m, 3H), 3.90-4.65 (m, 5H), 5.50-6.00 (m, 2H); 13C
NMR δ 17.9, 21.0, 21.8, 32.5 (d, J ) 7.5 Hz), 70.1 (d, J ) 160.0
Hz), 77.2, 125.4, 130.4; 31P NMR δ 15.2. Anal. Calcd for
C9H17O4P: C, 49.08; H, 7.79. Found: C, 49.04; H, 7.68.
Synthesis of compounds 4, 7, 8, and 12 was accomplished
in yields g90% by treating the respective R-hydroxy phospho-
nates (10 mmol) with SOCl2 according to the reported proce-
dure.2
(c) Syn th esis of 5-Ch lor ofu r fu r yl-Su bstitu ted Olefin s
13a -e: Typ ica l P r oced u r e for 13a . To a stirred suspension
of NaH (0.21 g, 8.75 mmol) in THF (20 mL) was added 4 (0.8
g, 3.02 mmol) in THF (20 mL) at 0 °C. After 30 min, the
mixture was brought to 25 °C, and 4-nitrobenzaldehyde (0.48
g, 3.17 mmol) in THF (20 mL) was added dropwise over a
period of 15 min. The mixture was stirred for 2 h, quenched
with cold water, and then extracted with ether. The ether layer
was dried (Na2SO4) and the solvent removed to obtain a
semisolid that was purified by column chromatography (silica
gel, hexane) to obtain 13a as an yellow solid: yield 0.75 g
4: mp 98-100 °C; 1H NMR δ 0.96, 1.03 (2s, 6H), 3.29 (d, J
) 22.0 Hz, 2H), 3.80 (dd, J ≈ 11.0, 11.0 Hz, 2H), 4.17 (dd, J ≈
11.0, 11.1 Hz, 2H), 6.10 (m, 1H), 6.25 (m, 1H); 13C NMR δ 21.2,
21.4, 25.7 (d, J ) 145.0 Hz), 32.4 (d, J ≈ 5.0 Hz), 75.7 (d, J ≈
7.0 Hz), 107.4, 111.0, 111.1, 144.6; 31P NMR δ 16.4. Anal. Calcd
for C10H14ClO4P: C, 45.37; H, 5.34. Found: C, 45.42; H, 5.38.
Crystals of 4 as a hydrate suitable for X-ray crystallography
were grown from CH2Cl2-hexane mixture in air by slow
evaporation of the solvent.
1
1
7: mp 120 °C; H NMR δ 1.08, 1.10 (2s, 6H), 3.87 (dd, J ≈
(g99%); mp 78 °C; H NMR δ 6.25 (d, J ) 3.8 Hz, 1H), 6.46
11.0 Hz, 12.0 Hz, 2H), 4.20 (dd, J ≈ 11.0, 12.0 Hz, 2H), 5.55
(d, J ≈ 3.0 Hz, 1H), 6.12 (ddd, J ≈ 3.0, 19.1, 19.1 Hz, 1H),
7.00, (ddd, J ≈ 8.5, 19.1, 19.1 Hz, 1H), 7.37 (br s, 5H); 13C
NMR δ 21.4, 21.6, 32.5 (d, J ) 6.0 Hz), 61.7 (d, J ) 25.0 Hz),
75.7 (d, J ) 4.5 Hz), 117.2 (d, J ) 186.0 Hz), 127.0, 127.7,
128.7, 129.0, 137.9, 150.7 (d, J ) 5.0 Hz); 31P NMR δ 11.2.
Anal. Calcd for C14H18ClO3P: C, 55.91; H, 6.04. Found: C,
55.87; H, 6.15.
(d, J ) 3.8 Hz, 1H), 6.92, 7.04 (AB qrt, J ) 16.2 Hz, 2H), 7.55
(d, J ) 8.8 Hz, 2H), 8.20 (d, J ) 8.8 Hz, 2H); 13C NMR δ 108.9,
112.9, 119.4, 123.7, 124.2, 124.7, 126.6, 143.2, 146.7, 151.9.
Anal. Calcd for C12H8ClNO3: C, 57.72; H, 5.61. Found: C,
57.76; H, 5.65.
The same molar quantities of the reactants were used to
prepare 13b-e (see the Supporting Information for charac-
terization data).
1
8: mp 120 °C; H NMR δ 1.08, 1.10 (2 s, 6H), 1.64 (d, J ≈
(d ) Syn th esis of th e Dien es 14a -f: Typ ica l P r oced u r e
for 14a . A mixture of 7 (0.50 g, 1.66 mmol), 2,4-dichloroben-
zaldehyde (0.29 g, 1.66 mmol), and K2CO3 (0.68 g, 4.90 mmol)
in xylene (10 mL) was heated under reflux for 24 h. After
removal of xylene, water was added and the mixture extracted
with ether (3 × 25 mL). Water wash, drying (Na2SO4), and
evaporation of the solvent gave a semisolid that was purified
by column chromatography (silica gel, hexane) to obtain 14a :
yield 0.49 g (95%); mp 129-131 °C; 1H NMR δ 6.98 (d, J ) 9.3
Hz, 1H), 7.11 (d, J ) 17.0 Hz, 1H), 7.20-7.80 (m, 9H); 13C
NMR δ 121.2, 125.5, 126.4, 126.5, 127.0, 127.3, 127.7, 128.5,
129.0, 129.9, 131.7. Anal. Calcd for C16H11Cl3: C, 62.06; H,
3.58. Found: C, 62.00; H, 3.60.
6.7 Hz, 3H), 3.87 (dd, J ) 11.0, 12.0 Hz, 2H), 4.20 (dd, J ≈
11.0, 11.0 Hz, 2H), 4.60 (dqrt, J ) 6.7, 6.7 Hz, 1H), 6.00 (dd,
J ) 19.0, 19.0 Hz, 1H), 6.85 (ddd, J ≈ 8.5, 19.0, 19.0 Hz, 1H);
13C NMR δ 21.5, 23.9, 32.5 (d, J ) 5.5 Hz), 55.6 (d, J ) 25.0
Hz), 75.7, 116.1 (d, J ) 186.5 Hz), 152.6; 31P NMR δ 11.3. Anal.
Calcd for C9H16ClO3P: C, 45.29; H, 6.77. Found: C, 45.15; H,
6.64.
12: mp 167-168 °C [starting from (OCH2CMe2CH2O)P(O)-
CH(OH)(C10H7), mp 172 °C; 31P NMR δ 13.1; 1H NMR δ 0.64,
1.06 (2s, 6H), 3.63-4.00 (m, 4H), 6.00 (d, J ) 11 Hz, 1H), 7.48-
8.15 (m, 7H)]; 1H NMR δ 0.89, 1.18 (2s, 6H), 3.99-4.20 (m,
4H), 6.01 (d, J ) 14.0 Hz, 1H), 7.44-8.10 (m, 7H); 13C NMR δ
(17) Zwierzak, A. Can. J . Chem. 1967, 45, 2501.
(18) McConnell, R. L.; Coover, H. W., J r. J . Org. Chem. 1959, 24,
630.
(19) (a) Gorenstein, D. G. Prog. NMR Spectrosc. 1983, 16, 1. (b)
Kumara Swamy, K. C.; Said, M. A.; Kumaraswamy, S.; Herbst-Irmer,
R.; Pu¨lm, M. Polyhedron 1998, 17, 3643.

Chlorophosphonates
J . Org. Chem., Vol. 65, No. 12, 2000 3737
Characterization data for 14b-f is available as Supporting
Information.
using graphite-monochromated Mo KR radiation (λ ) 0.710 73
Å). The structures were solved and refined by conventional
methods.20
(e) Syn th esis of Disu bstitu ted Acetylen es 15-18: Typi-
ca l P r oced u r e for 15b. To a mixture of the R-chlorophos-
phonate 11 (0.49 g, 1.73 mmol), ferrocene carboxaldehyde (0.37
g, 1.73 mmol), and DMSO (20 mL) was added sodium hydride
(0.12 g, 5.00 mmol). This mixture was then heated at 70 °C
for 14 h with stirring. The contents were transferred to a
separatory funnel, and ether (50 mL) and water (30 mL) were
added. The organic layer was washed with water, dried (Na2-
SO4), and filtered. Removal of the solvent followed by column
chromatography (hexane) afforded the acetylene 15b: yield
Cr ysta l d a ta : 4‚H2O; empirical formula, C10H16ClO5P;
formula weight, 282.65; crystal system, tetragonal; space
group, I4h; a ) 20.656(3) Å; b ) 20.656(3) Å; c ) 6.0420(12) Å;
V ) 2577.9(7) Å3; Z ) 8; density (calcd), 1.457 Mg m-3; µ )
0.427 mm-1; F(000) 1184; crystal size, 0.30 × 0.20 × 0.20 mm;
θ range, 1.97-27.51°; reflections collected, 5906; independent
reflections, 2964 [R(int) ) 0.1243]; attempts to solve the
structure in other space groups were not successful; refinement
method, full-matrix least-squares on F2; data/restraints/
parameters, 2964/0/162; goodness-of-fit on F2, 1.087; final R
indices [I > 2σ(I)], R1 ) 0.0693, wR2 ) 0.1759; absolute
structure parameter, -0.27(14); largest diff. peak and hole,
1
0.35 g (68%); mp 170 °C; IR (cm-1) 2206; H NMR δ 2.39 (s,
3H, CH3), 4.25 (s, 7H, ferrocene-H), 4.50 (s, 2H, ferrocene-H),
7.15 (d, J ) 12.0 Hz, 2H, Ar-H), 7.40 (d, J ) 12.0 Hz, 2H, Ar-
H); 13C NMR δ 65.7, 68.7, 70.0, 71.4 (ferrocenyl-C), 85.0 (Ct
C), 87.5 (CtC), 121.0, 129.1, 131.3, 137.7. Anal. Calcd for
0.511 and -0.458 e Å-3
.
7: empirical formula, C14H18ClO3P; formula wt, 300.70;
crystal system, orthorhombic; space group, Pbca; a ) 8.7813-
(18) Å; b ) 10.294(7) Å; c ) 33.362(10) Å; V ) 3016(2) Å-3; Z
) 8; density (calcd), 1.325 Mg m-3; µ ) 0.360 mm-1; F(000),
1264; crystal size, 0.3 × 0.2 × 0.1 mm; θ range, 2.44-24.98°;
reflections collected, 2644; independent reflections, 2644 [R(int)
) 0.0000]; refinement method, full-matrix least-squares on F2;
data/restraints/parameters, 2644/0/174; goodness-of-fit on F2,
1.076; final R indices [I > 2σ(I)], R1 ) 0.0680, wR2 ) 0.1717;
C
19H16Fe: C, 75.92; H, 5.32. Found: C, 76.02; H, 5.07.
Other compounds were obtained by taking the same molar
quantities of the reactants.
15a : yield 67%; mp 120 °C; 1H NMR δ 4.27 (s, 7H), 4.53 (s,
2H), 7.20-7.60 (m, 5H); 13C NMR δ 65.7, 68.8, 70.0, 71.4, 85.0,
87.5, 124.0, 127.7, 128.3, 131.4. Anal. Calcd for C18H14Fe: C,
75.47; H, 4.89. Found: C, 75.26; H, 4.81.
15c: yield 71%; mp 146 °C; IR (cm-1) 2211; 1H NMR δ 4.25
(s, 7H), 4.50 (s, 2H), 7.30-7.50 (qrt, 4H); 13C NMR δ 64.9, 69.0,
70.0, 71.5, 84.7, 89.6, 122.6, 128.6, 132.6, 133.6. Anal. Calcd
for C18H13ClFe: C, 67.40; H, 4.06. Found: C, 67.55; H, 4.05.
largest diff. peak and hole, 0.592 and -0.373 e A-3
.
13b: empirical formula, C12H8Cl2O; formula wt, 239.08;
crystal system, orthorhombic; space group, Pccn; a ) 26.895-
(5) Å; b ) 14.810(3) Å; c ) 5.579(4) Å; V ) 2222.3(17) Å-3; Z
) 8; density (calcd), 1.429 Mg m-3; µ ) 0.551 mm-1; F(000),
976; crystal size, 0.3 × 0.2 × 0.2 mm; θ range, 1.51 to 25.46°;
reflections collected, 2066; independent reflections, 2066 [R(int)
) 0.0000]; refinement method, full-matrix least-squares on F2;
data/restraints/parameters, 2066/0/136; goodness-of-fit on F2,
1.050; final R indices [I > 2σ(I)], R1 ) 0.0585, wR2 ) 0.1253;
largest diff. peak and hole, 0.328 and -0.250 e A-3. Further
details including an ORTEP drawing are given as Supporting
Information.
14a : empirical formula, C16H11Cl3; formula wt, 309.60;
crystal system, monoclinic; space group, P21/c; a ) 7.4728(15)
Å; b ) 11.6161(16) Å; c ) 16.270(3) Å; â ) 95.947(14)°; V )
1404.7(4) Å; Z ) 4; density (calcd), 1.464 Mg m-3; µ ) 0.634
mm-1; F(000), 632; crystal size, 0.3 × 0.2 × 0.2 mm; θ range,
2.16-24.96°; reflections collected, 2651; independent reflec-
tions, 2459 [R(int) ) 0.0320]; refinement method, full-matrix
least-squares on F2; data/restraints/parameters 2459/0/172;
goodness-of-fit on F2, 1.198; final R indices [I > 2σ(I)], R1 )
0.0312, wR2 ) 0.0945; largest diff. peak and hole, 0.200 and
-0.306 e Å-3. Further details are available as Supporting
Information.
1
15d : yield 35%; mp 160-162 °C; IR (cm-1) 2210; H NMR
δ 4.32 (s, 7H), 4.64 (s, 2H), 7.35-8.50 (m, 7H); 13C NMR δ 65.1,
69.0, 70.0, 71.6, 84.0, 93.2, 122.5, 125.3, 126.3, 126.6, 128.1,
128.3, 129.9, 133.3. Anal. Calcd for C22H16Fe: C, 78.57; H, 4.75.
Found: C, 78.50; H, 4.65.
17 (1.2 mmol of phosphonate used): (i) solid, isomer a ; yield
1
0.24 g, (64%); mp 88-90 °C; H NMR δ 4.22 (s, 5H), 4.35 (s,
2H), 4.92 (s, 2H), 5.76 (d, J ) 11.6 Hz, 1H), 6.50 (d, J ) 11.6
Hz, 1H), 7.29-7.50 (m, 5H); 13C NMR δ 69.5, 80.0, 90.0, 93.5,
104.0, 123.4, 128.0, 128.5, 131.2, 138.7. Anal. Calcd for C20H16
Fe: C, 76.92; H, 4.53. Found: C, 76.25; H, 4.77.
-
(ii): Liquid ∼0.10 g (27%) [isomer a + isomer b, ca. 1:2];
NMR data given below only for isomer b; 1H NMR δ 4.46 (m,
∼9H), 6.04 (d, J ) 15.8 Hz, 1H), 6.90 (d, J ) 15.8 Hz, 1H),
7.30-7.70 (m, 5H); 13C NMR δ 52.7, 67.0, 69.7, 70.3, 81.2,
104.9, 123.0, 127.8, 131.3, 140.7. See above for data on pure
isomer a .
16a (1.8 mmol of phosphonate used): yield 0.25 g (50%);
1
mp 106-108 °C (lit.8a mp 108-109 °C); H NMR 7.30-9.00;
13C NMR δ 86.7, 101.0, 117.5, 123.9, 125.8, 126.7, 126.9, 127.9,
128.9, 131.4, 131.8, 132.8. Anal. Calcd for C22H14: C, 94.88;
H, 5.03. Found: C, 94.48; H, 4.92.
16b (1.8 mmol of phosphonate used): yield 0.27 g (51%);
mp 110 °C; 1H NMR 2.41 (s, 3H), 7.25-8.65 (m, 13H); 13C NMR
δ 21.6, 85.9, 101.2, 117.7, 120.7, 125.7, 126.6, 126.9, 127.6,
128.8, 129.4, 131.3, 131.6, 132.7, 138.7. Anal. Calcd for
Ack n ow led gm en t. We thank the Department of
Science and Technology (New Delhi) for financial sup-
port as well as for setting up of the National Single
Crystal Diffractometer Facility at the University of
Hyderabad. K.C.K. thanks the AvH Foundation for
donation of equipment.
C
23H16: C, 95.52; H, 5.48. Found: C, 95.40; H, 5.38.
16c (3.2 mmol of phosphonate used): yield 0.53 g (53%);
mp 147-148 °C; IR (cm-1) 2197 (vw); 1H NMR 7.40-8.60 (m);
13C NMR δ 87.4, 99.6, 116.9, 122.2, 125.7, 126.7, 128.0, 128.8,
128.9, 131.2, 132.7, 132.8, 134.5. Anal. Calcd for C22H13Cl: C,
84.49; H, 4.16. Found: C, 84.28; H, 4.02.
Su p p or tin g In for m a tion Ava ila ble: X-ray structure
solution and refinement data for compounds 4‚H2O, 7, 13b,
and 14a and ORTEP drawings of 13b and 14a ; characteriza-
tion data for 13b-13e and 14b-14f. This material is available
free of charge via the Internet at http://pubs.acs.org.
18 (1.8 mmol of phosphonate used): yield 0.15 g (27%); mp
120-122 °C; 1H NMR 6.74 (d, J ) 16.2 Hz, 1H), 7.38-8.65
(m, 15H); 13C NMR δ 87.5, 101.0, 108.5, 117.6, 125.7, 126.5,
126.6, 126.8, 127.7, 128.7, 128.8, 131.3, 132.6, 136.5, 141.3.
Anal. Calcd for C24H16: C, 94.74; H, 5.26. Found: C, 94.75; H,
5.35.
J O991946Y
(f) X-r a y Cr ysta llogr a p h y. A suitable crystal of 4‚H2O, 7,
13b, or 14a was mounted on a glass fiber, and X-ray data
collected at 293 K on an Enraf-Nonius MACH3 diffractometer
(20) SHELX-97, A package for structure solution and refinement,
Sheldrick, G. M., University of Go¨ttingen, Go¨ttingen, Germany, 1997.