References and Notes
1
Dewick PM.
Medicinal Natural Products
2nd
ed.:
John Wiley and Sons;
Chichester:
2002.
2a
Tietze LF.
Steinmetz A.
Balkenhohl F.
Bioorg. Med. Chem. Lett.
1997,
71303
2b
Brooking P.
Doran A.
Grimsey P.
Hird NW.
Maclachlan WS.
Vimil M.
Tetrahedron
Lett.
1999,
40:
1405
2c
Grosche P.
Holtzel A.
Walk TB.
Trautwein AW.
Jung G.
Synthesis
1999,
1961
2d
Watson SP.
Wilson RD.
Judd DB.
Richards SA.
Tetrahedron
Lett.
1997,
38:
9065
3
Regan J.
Breitfelder S.
Cirillo P.
Gilmore T.
Graham AG.
Hickey E.
Klaus B.
Madwed J.
Moriak M.
Moss N.
Pargellis C.
Paw S.
Proto A.
Swinamer A.
Tang L.
Torcellini C.
J.
Med. Chem.
2002,
45:
2994
4
Haufel J.
Breitmaier E.
Angew. Chem., Int. Ed. Engl.
1974,
13:
604
5
Wustrow DJ.
Capiris T.
Rubin R.
Knobelsdorf JA.
Akunne H.
Davis MD.
Mackenzic R.
Pugsley TA.
Zoski KT.
Heffiner TG.
Wise LD.
Bioorg. Med. Chem. Lett.
1998,
8:
2067
6
Menozzi G.
Mosti L.
Fossa P.
Mattioli F.
Ghia M.
J.
Heterocycl. Chem.
1997,
34:
963
7
Soto L.
Legros JP.
Molla MC.
Garcia J.
Acta Crystallogr., Sect. B:
Struct. Sci.
1987,
43:
834
8
Sakai K.
Tomita Y.
Ue T.
Goshima K.
Ohminato M.
Tsubomura T.
Matsumoto K.
Ohmura K.
Kawakami K.
Inorg.
Chim. Acta
2000,
64:
297
9
Ona GB.
Moreno V.
Font-Bardia M.
Solans X.
Perez JM.
Alonso C.
J. Inorg. Biochem.
1999,
75:
205
10
Elguero J.
Comprehensive Heterocyclic Chemistry
Pergamon
Press;
Oxford:
1984.
11
Peruncheralathan S.
Khan TA.
Ila H.
Jun Ja Paa H.
J.
Org. Chem.
2005,
70:
10030
12
Giacomelli G.
Porcheddu A.
Salaris M.
Taddei M.
Eur. J. Org. Chem.
2003,
537
13
Aggarwal VK.
Vicente J.
Bonnert RV.
J.
Org. Chem.
2003,
68:
5381
14
Wolkoff P.
Can.
J. Chem.
1975,
53:
1333
15
Huisgen R.
Grashey R.
Knupfer H.
Kunz R.
Chem Ber.
1964,
97:
1085
16
Yavari I.
Khalili G.
Helv. Chim. Acta
2010,
93:
277
17
General Procedure
for the Synthesis of Compound 4
To
a stirred solution of P(OR)3 (1 mmol) and hydrazonyl chloride 3 (1 mmol) in CH2Cl2 (5
mL) was added acetylenic ester 2 (1 mmol)
at r.t. After completion of the reaction (10 h), as indicated by
TLC (hexane-EtOAc, 5:1), the solvent was removed under
reduced pressure, and the light cream residue was separated by silica
gel (Merck 230400 mesh) column chromatography using hexane-EtOAc
mixture as eluant to afford the pure products.
Selected Spectroscopic Data
Compound 4a: colorless crystals, mp 115-117 ˚C.
IR (KBr): 1741 (C=O), 1609, 1599, 1548, 1498, 1459, 1388,
1264 (P=O), 1234, 1172, 1054, 1051, 766, 693, 547 cm-¹. ¹H NMR
(500.1 MHz, CDCl3): δ = 1.12 (t, ³
J = 7.1 Hz,
3 H, Me), 1.20 (t, ³
J = 7.1
Hz, 3 H, Me), 3.61 (d, ³
J = 10.9
Hz, 3 H, POMe), 3.97 (d, ³
J = 10.8 Hz,
3 H, POMe), 4.06-4.11 (m, 1 H, OCH2), 4.15 (q, ³
J = 7.1 Hz,
2 H, OCH2), 4.22-4.28 (m, 1 H, OCH2),
5.43 (d, ³
J = 25.4 Hz,
1 H, CH), 6.93 (t, ³
J = 7.3 Hz,
1 H, CH), 7.11 (d, ³
J = 8.3
Hz, 2 H, 2 × CH), 7.27-7.33 (m,
3 H, 3 × CH), 7.35-7.37 (m,
2 H, 2 × CH), 8.01 (d, ³
J = 7.4 Hz,
2 H, 2 × CH). ³¹P
NMR (202 MHz, CDCl3): δ = 18.5. ¹³C
NMR (125.6 MHz, CDCl3): δ = 13.5 (Me),
13.8 (Me), 54.2 (d, ²
J = 6.9
Hz, POMe), 55.1 (d, ²
J = 6.0
Hz, POMe), 62.0 (OCH2), 62.8 (OCH2), 67.5
(d, ¹
J = 141.9
Hz, C), 69.8 (d, ³
J = 4.0
Hz, CH), 113.5 (2 × CH), 120.5 (CH), 127.2
(2 × CH), 128.0 (2 × CH),
128.6 (CH), 129.0 (2 × CH), 131.0 (C),
142.3 (C), 143.2 (C), 166.3 (C=O), 167.3 (d, ³
J = 17.0 Hz,
C=O). MS (EI): m/z = 474
(5) [M+], 429 (15), 77 (45),
71 (65), 57 (100), 43 (80). Anal. Calcd for C23H27N2O7P
(474.44): C, 58.23; H, 5.74; N, 5.90. Found: C, 58.47; H, 5.42;
N, 5.71.
Compound 4b:
yellow oil, yield 0.42 g (88%). IR (KBr): 1744 (C=O),
1596, 1498, 1432, 1383, 1256 (P=O), 1204, 1161, 1042, 1016,
971, 818, 745, 547 cm-¹. ¹H
NMR (500.1 MHz, CDCl3): δ = 1.02 (t, ³
J = 7.0 Hz,
3 H, Me), 1.34 (d, ³
J = 7.1
Hz, 3 H, Me), 2.35 (s, 3 H, Me), 3.67-3.70 (m, 6 H, 2 OMe),
3.93-4.03 (m, 2 H, POCH2), 4.31-4.36
(m, 2 H, POCH2), 5.42 (d, ³
J = 25.1 Hz,
1 H, CH), 6.90 (t, ³
J = 7.3 Hz,
1 H, CH), 7.07 (d, ³
J = 8.0
Hz, 2 H, 2 × CH), 7.15 (d, ³
J = 8.1 Hz,
2 H, 2 × CH), 7.27-7.30 (m,
2 H, 2 × CH), 7.80 (d, ³
J = 8.2 Hz,
2 H, 2 × CH). ³¹P
NMR (202 MHz, CDCl3): δ = 18.6. ¹³C
NMR (125.6 MHz, CDCl3): δ = 15.8 (d, ²
J = 6.3 Hz,
Me), 16.3 (d, ²
J = 5.7
Hz, Me), 21.3 (Me), 52.8 (OMe), 53.3 (OMe), 63.8 (d, ²
J = 6.9 Hz,
POCH2), 64.7 (d, ²
J = 6.2
Hz, POCH2), 67.6 (d, ¹
J = 141.4
Hz, C), 69.7 (d, ²
J = 4.0
Hz, CH), 113.1 (2 × CH), 120.2 (CH),
127.1 (2 × CH), 128.1 (C), 128.8 (2 × CH),
129.1 (2 × CH), 138.8 (C), 142.4 (d, ³
J = 6.4 Hz,
C), 143.3 (C), 167.1 (C=O), 168.2 (d, ³
J = 16.6 Hz,
C=O). MS (EI): m/z = 488
(5) [M+], 457 (10), 77 (30),
57 (100), 43 (70). Anal. Calcd for C24H29N2O7P
(488.47): C, 59.01; H, 5.98; N, 5.73. Found: C, 59.45; H, 5.41;
N, 5.47.
Compound 4c: yellow oil,
yield: 0.43 g (90%). IR (KBr): 1746 (C=O), 1597,
1572, 1497, 1433, 1384, 1256 (P=O), 1162, 1043, 1016, 972,
829, 745 cm-¹. ¹H
NMR (500.1 MHz, CDCl3): δ = 1.03 (t, ³
J = 7.0 Hz,
3 H, Me), 1.35 (t, ³
J = 7.0 Hz,
3 H, Me), 3.68-3.70 (m, 6 H, 2 OMe), 3.96-4.02
(m,
2 H, POCH2), 4.32-4.37 (m, 2 H,
POCH2), 5.41-5.43 (m, ³
J = 25.1 Hz,
1 H, CH), 6.92 (t, ³
J = 7.2
Hz, 1 H, CH), 7.08 (d, ³
J = 8.0
Hz, 2 H, 2 × CH), 7.26-7.32
(m, 4 H, 4 × CH), 7.94 (d, ³
J = 8.6 Hz,
2 H, 2 × CH). ³¹P
NMR (202 MHz, CDCl3): δ = 18.7. ¹³C
NMR (125.6 MHz, CDCl3): δ = 15.8 (d, ²
J = 6.1 Hz,
Me), 16.3 (Me), 21.2 (d, ²
J = 5.7
Hz, Me), 52.9 (OMe), 53.4 (OMe), 63.8 (d, ²
J = 7.2 Hz,
POCH2), 64.9 (d, ²
J = 6.2
Hz, POCH2), 67.5 (d, ¹
J = 140.5
Hz, C), 69.8 (d, ³
J = 3.6
Hz, CH), 113.3 (2 × CH), 120.7 (CH),
128.2 (2 × CH), 128.4 (2 × CH),
129.1 (2 × CH), 129.5 (C), 134.5 (C),
141.3 (C), 142.9 (C), 166.8 (C=O), 168.1 (d, ³
J = 16.9 Hz,
C=O). MS (EI): m/z = 508
(5) [M+], 447 (15), 77 (45), 57
(100), 43 (75). Anal. Calcd for C23H26N2O7PCl
(508.88): C, 54.28; H, 5.15; N, 5.50. Found: C, 54.71; H, 5.39;
N, 5.21.
18
Burnett AMN.
Johnson CK.
ORTEP
III, Report ORNL-6895
Oak Ridge National Laboratory;
Tennessee:
1996.
19 A referee of this paper suggested
a mechanistic alternative, involving the 1,3-dipolar cycloaddition
of a nitrilimine (formed by extrusion of HCl from the hydrazonoyl chlorides)
to the P-substituted fumarate (product of the reaction of HCl, the
phosphite, and the acetylenedi-carboxylate). Although we are unable
to rule out this possibility, we prefer the mechanism shown in Scheme
[²]
.