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Supplementary data
Wiley and Sons: Chichester, 2007.
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Examples, Third Edition; SAS Institute Inc: Cary, NC, 2007.
Supplementary data associated with this article can be found, in
13. Brandvik, P. J. Chemometr. Intell. Lab. Syst. 1998, 42, 51–61.
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15. General procedure for the enzymatic kinetic resolution: To a 100 mL steel reactor
(TharÒ
)
were added the appropriate 1-(phenylchalcogene)propan-2-ol
Reference and notes
(1 mmol) and CAL-B (100 mg). The supported enzyme was involved by a
porous metallic membrane fixed in the extremity of the stirring rod. The CO2
was introduced into the reactor until the desired pressure was reached, when
the adequate temperature was adjusted to reach the supercritical point. After
that, vinyl acetate (1 mL) was introduced into the system by means of a high-
1. (a) Rayner, C. M. Org. Process. Res. Dev. 2006, 11, 121–132; (b) Leitner, W. Acc.
Chem. Res. 2002, 35, 746–756; (c) Beckman, E. J. J. Supercrit. Fluids 2004, 28,
121–191.
2. Hobbs, H. R.; Thomas, N. R. T. Chem. Rev. 2007, 107, 2786–2820.
3. (a) Costa, C. E.; Clososki, G. C.; Barchesi, H. B.; Zanotto, S. P.; Nascimento, M. G.;
Comasseto, J. V. Tetrahedron: Asymmetry 2004, 15, 3945–3954; (b) Dos Santos,
A. A.; Costa, C. E.; Princival, J. L.; Comasseto, J. V. Tetrahedron: Asymmetry 2006,
17, 2252–2259; (c) Da Costa, C. E. Biotransformações na obtenção de hidróxi-
selenetos e hidróxi-teluretos quirais. São Paulo, 2007. PhD Thesis, Instituto de
Química-Universidade de São Paulo.
4. (a) Andrade, L. H.; Silva, A. V. Tetrahedron: Asymmetry 2008, 19, 1175–1181; (b)
Andrade, L. H.; Silva, A. V.; Pedrozo, E. C. Tetrahedron Lett. 2009, 50, 4331–4334.
5. For a review see: Comasseto, J. V.; Gariani, R. A. Tetrahedron 2009, 65, 8447–
8459.
6. See for example: Pellissier, H. Tetrahedron 2007, 63, 1297–1330.
7. Back, T. G. Organoselenium Chemistry; Oxford University Press: Oxford, UK,
1999.
pressure valve equipped with
a loop (500 lL). The mixture was stirred
(330 rpm) for 163 min and then CO2 was allowed to evaporate, the product
being collected in a glass trap. The residue was then separated by flash column
chromatography in silica gel eluting with hexane/ethyl acetate (4:1).
Compound (S)-1a: (CAS = 67253-47-8), yellow oil, yield = 80.6 mg (48%);
17
½
a 2D1
ꢀ
+55.6° (c 1.0, CHCl3), ee = 98.1%; Lit.
½ ꢀ +60.6° (c 1.0, CHCl3). Spectral
a 2D0
data in accordance with those of the literature.17 Compound (R)-2a:
(CAS = 136656-71-8), yellow oil, yield = 33.6 mg (40%); +1.0° (c 1.0,
½ ꢀ
a 2D1
½ ꢀ +0.5° (c 1.0, CHCl3) Spectral data in accordance
a 2D0
17
CHCl3), ee = 96.6%; Lit.
with those of the literature.17 Compound (S)-1b: (CAS = 70678-11-4), yellow
oil, yield = 82.7 mg (38.5%); ½ ꢀ +49.1° (c 1.0, CHCl3), ee = 92.5%; Lit.
a 2D1
3a
½ ꢀ +56° (c 1.0, CH2Cl2), ee = >99%. Spectral data in accordance with those of
a 2D1
the literature.3a Compound (R)-2b: (CAS = 834882-67-6), yellow oil,
yield = 102.8 mg (40%); ½a D21
ꢀ
+13.0° (c 1.0, CHCl3), ee = 97.0%; Lit.
(c 1.0, CH2Cl2), ee = >99%. Spectral data in accordance with those of the
(CAS = 926647-66-7),
-35.5° (c 1.0, CH2Cl2), ee = 92.0%; Lit.
(c 1.0, CH2Cl2), ee = >99%. Spectral data in accordance with those of the
½ ꢀ ꢁ7°
a 2D1
3a
8. Petragnani, N.; Stefani, H. A. Tellurium in Organic Synthesis, second ed.; Elsevier:
Amsterdam, 2007.
literature.3a
Compound
(S)-1c:
yellow
oil,
9. The biological importance of sulfur compounds deserves comments. Selenium
is an essential trace element, which is present in important enzymes of
mammalians. Several non-natural compounds of selenium and tellurium
mimic the activity of one of these enzymes, the gluthatione peroxidase. See
for example: Alberto, E. E.; Nascimento, V.; Braga, A. L. J. Braz. Chem. Soc. 2010,
21, 2032–2041. The study of the biological activity of organic compounds of
tellurium is considered an emerging research area: Ba, L. A.; Döring, M.; Jamier,
V.; Jacob, C. Org. Biomol. Chem., 2010, 8, 4203–4216.
yield = 105.4 mg (40.0%); ½a D22
ꢀ
½ ꢀ +5°
a 2D8
3b
literature.3b
Compound
(R)-2c:
(CAS = 926648-04-6),
yellow
oil,
yield = 117.6 mg (38.5%); ½a D22
ꢀ
ꢁ6.1° (c 1.0, CH2Cl2), ee = 94.0%; Lit.
½ ꢀ ꢁ6°
a 2D8
3b
(c 1.0, CH2Cl2), ee = >99%. Spectral data in accordance with those of the
literature.3b
16. Ferrarini, R. S.; Dos Santos, A. A.; Comasseto, J. V. Tetrahedron Lett. 2010, 51,
6843–6846. and corrigendum: Tetrahedron Lett. 2011, 52, 2001.
17. Goergens, U.; Schneider, M. P. J. Chem. Soc. Chem. Commun. 1991, 1064–1066.
10. Doehlert, D. H.; Klee, V. L. Discrete Mathematics 1972, 2, 309–334. For details
see Supplementary data.