3350
K. C. Kumara Swamy et al. / Tetrahedron Letters 46 (2005) 3347–3351
Zakharov, S. V.; Nuriazdanova, G. Kh.; Garifzyanov, A.
R.; Galkin, V. I.; Cherkasov, R. A. Russ. J. Gen. Chem.
2004, 74, 873; Zh. Obshch. Khim. 2004, 74, 946; (p) Joly,
G. D.; Jacobsen, E. N. J. Am. Chem. Soc. 2004, 126, 4102;
(q) Kaboudin, B.; Saadati, F. Synthesis 2004, 1249.
3. (a) Engelmann, M.; Pikl, J. US Patent 2.304.156, 1942.
Chem. Abstr. 1943, 37, 20212; (b) Birum, G. H. J. Org.
Chem. 1974, 39, 209; (c) Oleksyszyn, J. Synthesis 1980,
722.
4. (a) Dai, Q.; Chen, R.; Zhang, C.; Liu, Z. Synthesis 1998,
405; (b) Xu, J.; Ma, Y.; Duan, L. Heteroat. Chem. 2000,
11, 417; (c) Praveen Kumar, K.; Muthiah, C.; Kumara-
swamy, S.; Kumara Swamy, K. C. Tetrahedron Lett. 2001,
42, 3219; (d) Dimukhametov, M. N.; Bajandina, E. V.;
Davydova, E. Y.; Litvinov, I. A.; Gubaidullin, A. T.;
Dobrynin, A. B.; Zyablikova, T. A.; Alfonsov, V. A.
Heteroat. Chem. 2003, 14, 56 .
5. Stirring PCl3 with 2,2-dimethyl-1,3-propanediol (neat, 8 h)
followed by distillation under low vacuum affords 3 in 80–
85% yields. For earlier preparations, see: (a) Zwierzak, A.
Can. J. Chem. 1967, 45, 2501; (b) Stec, W.; Zwierzak, A.
Can. J. Chem. 1967, 45, 2513; (c) Muthiah, C.; Praveen
Kumar, K.; Aruna Mani, C.; Kumara Swamy, K. C.
J. Org. Chem. 2000, 65, 3733.
For the formation of 6a–i, 7a–e, and 8a–c, one possible
pathway is the in situ generation of the imine
EtO2CN@CHAr, with 3 acting as a dehydrating
agent;4b the resulting phosphite II could then react with
the imine. However, since the reaction of phosphites
with imines is generally sluggish, there is a possibility
that the HCl present may act as an activating agent.
Also, since direct formation of a-substituted phospho-
nates (RO)2P(O)CH(X)Ar from the corresponding
phosphites (RO)2PX and ArCHO is possible,4c,13 mech-
anistic aspects of the formation of compounds 6–8 and
14 need to be probed further, in particular with respect
to the role of acid (HCl) or amine hydrochloride.
Acknowledgements
We thank (i) Department of Science and Technology
(DST), New Delhi for financial support, (ii) DST
(New Delhi) for Single Crystal Diffractometer facilities,
and (iii) The UPE program under UGC (New Delhi) for
equipment, and (iv) CSIR for a fellowship to K.S.K.
6. Huttenloch, O.; Spieler, J.; Waldmann, H. Chem. Eur. J.
2000, 6, 671.
7. Lucas, H. J.; Mitchell, F. W., Jr.; Scully, C. N. J. Am.
Chem. Soc. 1950, 72, 5491.
Supplementary data
8. Compound 6f: Benzamide (1.36g, 11.3 mmol) was added
to freshly distilled 3 (1.91 g, 11.3 mmol) and the mixture
heated at 130 °C under nitrogen with continuous swirling
to afford a homogeneous liquid (15–20 min). This was
cooled (25 °C) to give a solid, 9-anthraldehyde (2.33 g,
11.3 mmol) was added in one portion and the mixture
Supplementary data associated with this article can be
parameters for 10, CIF files for compounds 6f, 10, and
14a and further experimental data and figures of the
31P NMR spectra are included.
shaken vigorously.
A
slightly exothermic reaction
occurred and a viscous liquid was formed in 3 min (mostly
the required compound). This was dissolved in dichloro-
methane–toluene (1:1; 10 mL) mixture and the solvent was
allowed to evaporate in open air to give crystalline 6f.
Yield: 4.41 g (85%). Mp: 276–278 °C, IR (cmꢀ1): 3337,
1649, 1514, 1271, 1057. 1H NMR (200 MHz, CDCl3): d
0.81, 1.03 (2s, 6H, 2CH3), 3.34 and 3.70 (2t, 3J(P–
References and notes
1. Selected references: (a) Kukhar, V. P.; Hudson, H. R.
Aminophosphonic and Aminophosphinic Acids—Chemistry
2
and Biological Activity; John Wiley
&
Sons:
H) ꢁ J(H–H) = 10.3 Hz, 2H, OCHAHB), 4.21 (ꢁd,
Chichester, 2000; (b) Kafarski, P.; Lejczak, B. Curr.
Med. Chem.—Anti-cancer Agents 2001, 1, 301; (c) Klesz-
czynska, H.; Sarapuk, J. Cell. Biol. Mol. Lett. 2001, 6, 83;
(d) Quin, L. D.; Quin, G. S. Comp. Biochem. Physiol.,
Biochem. Mol. Biol. 2001, 128B, 173; (e) Obojska, A.;
Lejczak, B. Appl. Microbiol. Biotechnol. 2003, 62, 557; (f)
Bielecki, K.; Sarapuk, J.; Kleszczynska, H. Z. Naturforsch.
2004, 59C, 515.
2J(H–H) = 10.7 Hz, 2H, OCH2), 7.36–8.50 (m, 15H, Ar–
H + P–CH) 8.85 (m, 1H, NH). 13C NMR (50 MHz,
CDCl3): d 21.1, 21.5 (2CH3), 32.4 (d, 3J(P–C) = 6.2 Hz,
CMe2), 45.6(d, 1J(P–C) = 148.4 Hz, P–CH), 76.4 (d, 2J(P–
C) = 5.9 Hz, OCH2) 125.0, 126.8, 127.2, 128.5, 129.5,
129.7, 131.8, 133.5,167.0. 31P NMR (81 MHz, CDCl3): d
16.9. Anal. Calcd for C27H26NO4P: C, 70.57; H, 5.70; N,
3.04. Found: C, 70.45; H, 5.68; N, 3.01.
2. Selected references: (a) Smith, A. B., III; Yager, K. M.;
Taylor, C. M. J. Am. Chem. Soc. 1995, 117, 10879; (b)
Lefebvre, I. M.; Evans, S. A., Jr. J. Org. Chem. 1997, 62,
7532; (c) Groeger, H.; Saida, Y.; Sasai, H.; Yamaguchi,
K.; Martens, J.; Shibasaki, M. J. Am. Chem. Soc. 1998,
120, 3089; (d) Qian, C.; Huang, T. J. Org. Chem. 1998, 63,
4125; (e) Burk, M. J.; Stammers, T. A.; Straub, J. A. Org.
Lett. 1999, 1, 387; (f) Davis, F. A.; McCoull, W.; Titus, D.
D. Org. Lett. 1999, 1, 1053; (g) Ranu, B. C.; Hajra, A.;
Jana, U. Org. Lett. 1999, 1, 1141; (h) Yadav, J. S.; Reddy,
B. V. S.; Madan, Ch. Synlett 2001, 1131; (i) Haak, E.;
Bytschkov, I.; Doye, S. Eur. J. Org. Chem. 2002, 457; (j)
Saidi, M. R.; Azizi, N. Synlett 2002, 1347; (k) Ranu, B. C.;
Hajra, A. Green Chem. 2002, 4, 551; (l) Yadav, J. S.;
Reddy, B. V. S.; Sreedhar, P. Green Chem. 2002, 4, 436;
(m) Chandrasekhar, S.; Narsihmulu, Ch.; Sultana, S. S.;
Saritha, B.; Prakash, S. J. Synlett 2003, 505; (n) Davis, F.
A.; Prasad, K. R. J. Org. Chem. 2003, 68, 7249; (o)
Compound 14a: To R-(+)-4 (1.44 g, 4.1 mmol) was added
urethane (0.36g, 4.1 mmol) and the mixture heated at
80 °C under nitrogen with continuous swirling to yield a
homogeneous liquid (ca. 10 min). Upon cooling to 25 °C,
this became a solid mass. Benzaldehyde (0.43 g, 4.1 mmol,
0.4 mL) was added in one portion and the mixture heated
at 80 °C under nitrogen for 15 min to give a viscous liquid
that solidified upon cooling. A 31P NMR examination
revealed that this solid was a mixture of diastereomers of
14a (d 30.1 (65%) and 29.5 (35%)). One of these was
separated in pure form by column chromatography using
hexane–ethyl acetate (3:1). Yield: 1.4 g (70%). Yield (single
diastereomer): 0.20 g (10%): Mp: 230–232 °C. IR (cmꢀ1):
3275, 1682, 1510, 1300, 1224, 1072, 964. 1H NMR
(200 MHz, CDCl3): d 1.13 (t, 3J(H–H) = 7.2 Hz, 3H,
CH2CH3), 4.03 (q, 3J(H–H) = 7.2 Hz, 2H, OCH2CH3),
5.40 (m, 2H, P–CH + NH), 6.96–8.05 (m, 16H, Ar–H).
1
13C NMR (50 MHz, CDCl3): d 14.4 (CH3), 53.1 (d, J(P–