-
1
-
-
0242298257
-
-
amphidinolide K
-
(a) Mas, G.; González, L.; Vilarrasa, J. Tetrahedron Lett. 2003, 44, 8805 (amphidinolide K).
-
(2003)
Tetrahedron Lett
, vol.44
, pp. 8805
-
-
Mas, G.1
González, L.2
Vilarrasa, J.3
-
2
-
-
25444476745
-
-
amphidinolide K
-
(b) Andreou, T.; Costa, A. M.; Esteban, L.; González, L.; Mas, G.; Vilarrasa, J. Org. Lett. 2005, 7, 4083 (amphidinolide K).
-
(2005)
Org. Lett
, vol.7
, pp. 4083
-
-
Andreou, T.1
Costa, A.M.2
Esteban, L.3
González, L.4
Mas, G.5
Vilarrasa, J.6
-
3
-
-
33947593955
-
-
amphidinolide X/Y
-
(c) Rodríguez-Escrich, C.; Olivella, A.; Urpí, F.; Vilarrasa, J. Org. Lett. 2007, 9, 989 (amphidinolide X/Y).
-
(2007)
Org. Lett
, vol.9
, pp. 989
-
-
Rodríguez-Escrich, C.1
Olivella, A.2
Urpí, F.3
Vilarrasa, J.4
-
4
-
-
39349115816
-
-
Li and Na enolates of type 3, when the temperature is raised up to -30°C to increase the reaction rates, begin to decompose.
-
Li and Na enolates of type 3, when the temperature is raised up to -30°C to increase the reaction rates, begin to decompose.
-
-
-
-
5
-
-
0000504848
-
-
(a) Evans, D. A.; Bilodeau, M. T.; Somers, T. C.; Clardy, J.; Cherry, D.; Kato, Y. J. Org. Chem. 1991, 56, 5750.
-
(1991)
J. Org. Chem
, vol.56
, pp. 5750
-
-
Evans, D.A.1
Bilodeau, M.T.2
Somers, T.C.3
Clardy, J.4
Cherry, D.5
Kato, Y.6
-
6
-
-
0026553741
-
-
application to the total synthesis of calyculin
-
(b) Evans, D. A.; Gage, J. R.; Leighton, J. L.; Kim, A. S. J. Org. Chem. 1992, 57, 1961 (application to the total synthesis of calyculin).
-
(1992)
J. Org. Chem
, vol.57
, pp. 1961
-
-
Evans, D.A.1
Gage, J.R.2
Leighton, J.L.3
Kim, A.S.4
-
7
-
-
39349113234
-
-
Ph.D. Thesis, Universitat de Barcelona
-
(c) Mas, G. Ph.D. Thesis, Universitat de Barcelona, 2000.
-
(2000)
-
-
Mas, G.1
-
8
-
-
0033452058
-
-
For the reaction of enolates of trisubstituted oxazolidinones with nitroalkenes, see
-
(d) For the reaction of enolates of trisubstituted oxazolidinones with nitroalkenes, see: Brenner, M.; Seebach, D. Helv. Chim. Acta 1999, 82, 2365.
-
(1999)
Helv. Chim. Acta
, vol.82
, pp. 2365
-
-
Brenner, M.1
Seebach, D.2
-
9
-
-
0001449876
-
-
3-substituted acrylates, see: Shinohara, N.; Haga, J.; Yamazaki, T.; Kitazume, T.; Nakamura, S. J. Org. Chem. 1995, 60, 4363.
-
3-substituted acrylates, see: Shinohara, N.; Haga, J.; Yamazaki, T.; Kitazume, T.; Nakamura, S. J. Org. Chem. 1995, 60, 4363.
-
-
-
-
10
-
-
39349099236
-
-
8O). The results were parallel to those reported here.
-
8O). The results were parallel to those reported here.
-
-
-
-
11
-
-
0023885132
-
-
The TBS protecting group was chosen in view of its stability under the reaction conditions and the availability of specific cleavage methods. The OBn derivative decomposes before reacting, under similar conditions. The synthetic utility of the enolates of glycolate-derived oxazolidinones in other reactions, such as aldol reactions and alkylations, has been established: (a) Evans, D. A, Bender, S. L, Morris, J. J. Am. Chem. Soc. 1988, 110, 2506
-
The TBS protecting group was chosen in view of its stability under the reaction conditions and the availability of specific cleavage methods. The OBn derivative decomposes before reacting, under similar conditions. The synthetic utility of the enolates of glycolate-derived oxazolidinones in other reactions, such as aldol reactions and alkylations, has been established: (a) Evans, D. A.; Bender, S. L.; Morris, J. J. Am. Chem. Soc. 1988, 110, 2506.
-
-
-
-
12
-
-
0034644037
-
-
(b) Crimmins, M. T.; Emmitte, K. A.; Katz, J. D. Org. Lett. 2000, 2, 2165.
-
(2000)
Org. Lett
, vol.2
, pp. 2165
-
-
Crimmins, M.T.1
Emmitte, K.A.2
Katz, J.D.3
-
14
-
-
33748468588
-
-
Evans, D. A.; Urpí, F.; Somers, T. C.; Clark, J. S.; Bilodeau, M. T. J. Am. Chem. Soc. 1990, 112, 8215.
-
(1990)
J. Am. Chem. Soc
, vol.112
, pp. 8215
-
-
Evans, D.A.1
Urpí, F.2
Somers, T.C.3
Clark, J.S.4
Bilodeau, M.T.5
-
15
-
-
0032563845
-
-
(a) Prashad, M.; Har, D.; Kim, H.-Y.; Repic, O. Tetrahedron Lett. 1998, 39, 7067.
-
(1998)
Tetrahedron Lett
, vol.39
, pp. 7067
-
-
Prashad, M.1
Har, D.2
Kim, H.-Y.3
Repic, O.4
-
16
-
-
39349116696
-
-
4 was dissolved in phosphate-buffered water (pH 8); the reaction time was shortened to 30 min. Migration of the TBS group to the primary hydroxy group did not occur under these conditions.
-
4 was dissolved in phosphate-buffered water (pH 8); the reaction time was shortened to 30 min. Migration of the TBS group to the primary hydroxy group did not occur under these conditions.
-
-
-
-
17
-
-
0344242779
-
-
(a) Penning, T. D.; Djuric, S. W.; Haack, R. A.; Kalish, V. J.; Miyashiro, J. M.; Rowell, B. W.; Yu, S. S. Synth. Commun. 1990, 307.
-
(1990)
Synth. Commun
, pp. 307
-
-
Penning, T.D.1
Djuric, S.W.2
Haack, R.A.3
Kalish, V.J.4
Miyashiro, J.M.5
Rowell, B.W.6
Yu, S.S.7
-
19
-
-
39349097232
-
-
Also see ref 1b for complex substrates where undesired conjugate additions can take place
-
(c) Also see ref 1b for complex substrates where undesired conjugate additions can take place.
-
-
-
-
20
-
-
1442286555
-
-
(a) Miyazaki, T.; Han-ya, Y.; Tokuyama, H.; Fukuyama, T. Synlett 2004, 477.
-
(2004)
Synlett
, pp. 477
-
-
Miyazaki, T.1
Han-ya, Y.2
Tokuyama, H.3
Fukuyama, T.4
-
22
-
-
27844466269
-
-
The direct reduction of Weinreb amides to aldehydes is a standard. Since the pioneering work of Nahm and Weinreb (Nahm, S.; Weinreb, S. M. Tetrahedron Lett. 1981, 22, 3815), ca. 200 out of 500 papers have utilized DIBALH as the reducing agent, according to a SciFinder-based search, (b) Very often R*CO-Aux* are converted to R*CO-N(OMe)Me and then to R*CHO, but no examples are found of competition between the two first groups for nucleophiles.
-
The direct reduction of Weinreb amides to aldehydes is a standard. Since the pioneering work of Nahm and Weinreb (Nahm, S.; Weinreb, S. M. Tetrahedron Lett. 1981, 22, 3815), ca. 200 out of 500 papers have utilized DIBALH as the reducing agent, according to a SciFinder-based search, (b) Very often R*CO-Aux* are converted to R*CO-N(OMe)Me and then to R*CHO, but no examples are found of competition between the two first groups for nucleophiles.
-
-
-
-
23
-
-
0034622890
-
-
2 at -78°C, attacks both the endo and exo CO groups of acylated oxazolidinones, whereas only the exocyclic CO reacts in the case of their 5,5-dimethyl analogues (Super Quats): (a) Bull, S. D.; Davies, S. G.; Nicholson, R. L.; Sanganee, H. J.; Smith, A. D. Tetrahedron: Asymmetry 2000, 11, 3475.
-
2 at -78°C, attacks both the endo and exo CO groups of acylated oxazolidinones, whereas only the exocyclic CO reacts in the case of their 5,5-dimethyl analogues ("Super Quats"): (a) Bull, S. D.; Davies, S. G.; Nicholson, R. L.; Sanganee, H. J.; Smith, A. D. Tetrahedron: Asymmetry 2000, 11, 3475.
-
-
-
-
24
-
-
0041818295
-
-
To favor the selective attack on the hydroxamate, we have utilized ethereal solvents
-
(b) Bull, S. D.; Davies, S. G.; Nicholson, R. L.; Sanganese, H. J.; Smith, A. D. Org. Biomol. Chem. 2003, 1, 2886. To favor the selective attack on the hydroxamate, we have utilized ethereal solvents.
-
(2003)
Org. Biomol. Chem
, vol.1
, pp. 2886
-
-
Bull, S.D.1
Davies, S.G.2
Nicholson, R.L.3
Sanganese, H.J.4
Smith, A.D.5
-
25
-
-
0002884392
-
-
For the use of morpholine amides as an alternative to Weinreb amides, see: a
-
For the use of morpholine amides as an alternative to Weinreb amides, see: (a) Martín, R.; Romea, P.; Tey, C.; Urpí, F.; Vilarrasa, J. Synlett 1997, 1414.
-
(1997)
Synlett
, pp. 1414
-
-
Martín, R.1
Romea, P.2
Tey, C.3
Urpí, F.4
Vilarrasa, J.5
-
27
-
-
0033591193
-
-
(c) Sengupta, S.; Mondal, S.; Das, D. Tetrahedron Lett. 1999, 40, 4107.
-
(1999)
Tetrahedron Lett
, vol.40
, pp. 4107
-
-
Sengupta, S.1
Mondal, S.2
Das, D.3
-
28
-
-
0033992319
-
-
(d) Douat, C.; Heitz, A.; Martinez, J.; Fehrentz, J.-A. Tetrahedron Lett. 2000, 41, 37.
-
(2000)
Tetrahedron Lett
, vol.41
, pp. 37
-
-
Douat, C.1
Heitz, A.2
Martinez, J.3
Fehrentz, J.-A.4
-
29
-
-
0037067536
-
-
(e) Jackson, M. M.; Leverett, C.; Toczko, J. F.; Roberts, J. C. J. Org. Chem. 2002, 67, 5032.
-
(2002)
J. Org. Chem
, vol.67
, pp. 5032
-
-
Jackson, M.M.1
Leverett, C.2
Toczko, J.F.3
Roberts, J.C.4
-
30
-
-
0037073825
-
-
(f) Badioli, M.; Ballini, R.; Bartolacci, M.; Bosica, G.; Torregiani, E.; Marcantoni, E. J. Org. Chem. 2002, 67, 8938.
-
(2002)
J. Org. Chem
, vol.67
, pp. 8938
-
-
Badioli, M.1
Ballini, R.2
Bartolacci, M.3
Bosica, G.4
Torregiani, E.5
Marcantoni, E.6
-
31
-
-
0037122049
-
-
(g) Goodman, S. N.; Jacobsen, E. N. Angew. Chem., Int. Ed. 2002, 41, 4703.
-
(2002)
Angew. Chem., Int. Ed
, vol.41
, pp. 4703
-
-
Goodman, S.N.1
Jacobsen, E.N.2
-
32
-
-
8744303700
-
-
(h) Clark, C. T.; Milgram, B. C.; Scheldt, K. A. Org. Lett. 2004, 6, 3977.
-
(2004)
Org. Lett
, vol.6
, pp. 3977
-
-
Clark, C.T.1
Milgram, B.C.2
Scheldt, K.A.3
-
33
-
-
1842614850
-
-
and references cited therein
-
(i) Tosaki, S.; Horiuchi, Y.; Nemoto, T.; Ohshima, T.; Shibasaki, M. Chem. Eur. J. 2004, 10, 1527 and references cited therein,
-
(2004)
Chem. Eur. J
, vol.10
, pp. 1527
-
-
Tosaki, S.1
Horiuchi, Y.2
Nemoto, T.3
Ohshima, T.4
Shibasaki, M.5
-
34
-
-
14844333286
-
-
(j) Ruiz, J.; Ardeo, A.; Ignacio, R.; Sotomayor, N.; Lete, E. Tetrahedron 2005, 61, 3311.
-
(2005)
Tetrahedron
, vol.61
, pp. 3311
-
-
Ruiz, J.1
Ardeo, A.2
Ignacio, R.3
Sotomayor, N.4
Lete, E.5
-
36
-
-
34547927263
-
-
(l) Concellón, J. M.; Rodríguez-Solla, H.; Méjica, C.; Blanco, E. G. Org. Lett. 2007, 9, 2981.
-
(2007)
Org. Lett
, vol.9
, pp. 2981
-
-
Concellón, J.M.1
Rodríguez-Solla, H.2
Méjica, C.3
Blanco, E.G.4
-
37
-
-
39349093292
-
-
In our experiments with the morpholine amide (4b, which is less reactive than the Weinreb amide 4a, we preferred stopping the reactions at conversions of 80-90, recovering the unreacted starting material, rather than adding larger amounts of DIBALH or increasing the reaction times, as byproducts coming from the attack on the other CO carbon atoms could appear
-
(a) In our experiments with the morpholine amide (4b), which is less reactive than the Weinreb amide (4a), we preferred stopping the reactions at conversions of 80-90%, recovering the unreacted starting material, rather than adding larger amounts of DIBALH or increasing the reaction times, as byproducts coming from the attack on the other CO carbon atoms could appear,
-
-
-
-
38
-
-
39349092703
-
-
8O), that is 3 (R/OR = Me), was also cleaved successfully, in the same way. Independent studies regarding the reduction of morpholine amides to aldehydes will be reported in due course.
-
8O), that is 3 (R/OR = Me), was also cleaved successfully, in the same way. Independent studies regarding the reduction of morpholine amides to aldehydes will be reported in due course.
-
-
-
|