9
74
Synlett
Y.-S. Choi et al.
Letter
X.; Shi, F.; Deng, Y. Tetrahedron Lett. 2011, 52, 1334. (h) Zotova,
N.; Roberts, F. J.; Kelsall, G. H.; Jessiman, A. S.; Hellgardt, K.; Hii,
K. K. Green Chem. 2012, 14, 226.
(9) Microflow Reaction; General Procedure: The reactor (40 μL
stainless steel tubing) was heated to the reaction temperature
(100–200 °C). Solutions of alkyl halide (0.2 mmol) and primary
amine (0.2–0.4 mmol), each in DMF (10 mL), were used to fill up
the sample loops of the reagent injector and they were simulta-
neously introduced into the reactor by using pumps. By regulat-
ing the flow rate of the pumps (5 to 120 μL/min each), the reac-
tion mixture was collected at each reaction time (0.17 to 4 min).
Collected reaction mixtures were analyzed immediately by
using HPLC.
(
2) (a) Gawande, M. B.; Deshpande, S. S.; Satam, J. R.; Jayaram, R. V.
Catal. Commun. 2007, 8, 576. (b) Ju, Y.; Varma, R. S. Green Chem.
2004, 6, 219. (c) Romera, J. L.; Cid, J. M.; Trabanco, A. A. Tetrahe-
dron Lett. 2004, 45, 8797. (d) Singh, C. B.; Kavala, V.; Samal, A.
K.; Patel, B. K. Eur. J. Org. Chem. 2007, 1369.
(
3) (a) Salvatore, R. N.; Nagle, A. S.; Jung, K. W. J. Org. Chem. 2002,
67, 674. (b) Salvatore, R. N.; Schmidt, S. E.; Shin, S. I.; Nagle, A. S.;
Worrell, J. H.; Jung, K. W. Tetrahedron Lett. 2000, 41, 9705.
4) (a) Chiappe, C.; Pieraccini, D. Green Chem. 2003, 5, 193.
(10) Flask Reaction; General Procedure: To a solution of aniline
(0.1–0.2 mol) in DMF (1 L, heated at 150 °C), benzyl bromide
(0.1 mol) was added during 10 min. The reaction mixtures, col-
lected at defined time intervals, were analyzed immediately by
using HPLC.
(
(b) Chiappe, C.; Piccioli, P.; Pieraccini, D. Green Chem. 2006, 8,
277. (c) Monopoli, A.; Cotugno, P.; Cortese, M.; Calvano, C. D.;
Ciminale, F.; Nacci, A. Eur. J. Org. Chem. 2012, 3105.
5) (a) Hartman, R. L.; McMullen, J. P.; Jensen, K. F. Angew. Chem.
Int. Ed. 2011, 50, 7502. (b) Illg, T.; Löb, P.; Hessel, V. Bioorg. Med.
Chem. 2010, 18, 3707. (c) McMullen, J. P.; Jensen, K. F. Ann. Rev.
Anal. Chem. 2010, 3, 19. (d) Newman, S. G.; Jensen, K. F. Green
Chem. 2013, 15, 1456. (e) Seeberger, P.; Geyer, K.; Gustafsson, T.
Synlett 2009, 2382. (f) Wegner, J.; Ceylan, S.; Kirschning, A.
Chem. Commun. 2011, 47, 4583. (g) Wiles, C.; Watts, P. Green
Chem. 2012, 14, 38.
(
(11) General Remarks on the Microflow System: Pumps, reagent
injectors, pressure controller, product collector, and control
software from Syrris Asia system were used to construct the
microflow system. A stainless steel T connector (0.25 mm i.d.)
was placed at the junction of the two flow streams. The reactor
part consisted of stainless steel tubing (0.25 mm i.d. × 800 mm,
40 μL volume) coiled around an aluminum cylinder. Each part
of the system was connected with PTFE tubing (0.3–0.5 mm i.d).
The T junction and the cooling part were chilled to 0 °C to
reduce the reaction rate in these parts. Reaction temperature
was maintained only at the reactor part by the heater. Pressure
in the system was maintained at 7 bar by using a pressure con-
troller.
(
6) (a) Chambers, R. D.; Spink, R. C. H. Chem. Commun. 1999, 883.
(b) Glasnov, T. N.; Holbrey, J. D.; Kappe, C. O.; Seddon, K. R.; Yan,
T. Green Chem. 2012, 14, 3071. (c) Kawaguchi, T.; Miyata, H.;
Ataka, K.; Mae, K.; Yoshida, J. Angew. Chem. Int. Ed. 2005, 44,
2
(
413. (d) Liu, J.; Fitzgerald, A.; Mani, N. Synthesis 2012, 44, 2469.
e) Webb, D.; Jamison, T. F. Org. Lett. 2011, 14, 568. (f) Wiles, C.;
Watts, P.; Haswell, S. J. Tetrahedron Lett. 2007, 48, 7362.
g) Yoshida, J.; Nagaki, A.; Iwasaki, T.; Suga, S. Chem. Eng. Tech-
(12) (a) Rys, P. Acc. Chem. Res. 1976, 10, 345. (b) Rys, P. Angew. Chem.
Int. Ed. Engl. 1977, 12, 807.
(13) Nagaki, A.; Togai, M.; Suga, S.; Aoki, N.; Mae, K.; Yoshida, J. J. Am.
Chem. Soc. 2005, 127, 11666.
(
nol. 2005, 28, 259.
(
7) (a) de la Hoz, A.; Gómez, M.; Rodriguez, A.; Juan, A.; Moreno, A.
Synthesis 2012, 44, 2527. (b) Glasnov, T.; Kappe, C.; Reichart, B.
Synlett 2013, 24, 2393. (c) Kunz, H.; Koch, S.; Löwe, H. Synlett
(14) Weinstein, H.; Adler, R. J. Chem. Eng. Sci. 1967, 22, 65.
(15) (a) Baraldi, P. T.; Noël, T.; Wang, Q.; Hessel, V. Tetrahedron Lett.
2014, 55, 2090. (b) Bedore, M. W.; Zaborenko, N.; Jensen, K. F.;
Jamison, T. F. Org. Process Res. Dev. 2010, 14, 432. (c) Kobayashi,
H.; Driessen, B.; van Osch, D. J. G. P.; Talla, A.; Ookawara, S.;
Noël, T.; Hessel, V. Tetrahedron 2013, 69, 2885. (d) Newman, S.
G.; Gu, L.; Lesniak, C.; Victor, G.; Meschke, F.; Abahmane, L.;
Jensen, K. F. Green Chem. 2014, 16, 176.
2011, 1978. (d) Li, J.-X.; Jin, J.; Cai, M.-M. Synlett 2009, 2534.
(e) Nagaki, A.; Kim, H.; Yoshida, J. Angew. Chem. 2008, 120,
7951. (f) Wahab, B.; Ellames, G.; Passey, S.; Watts, P. Tetrahedron
2010, 66, 3861.
(8) Goodman, J. M.; Kirby, P. D.; Haustedt, L. O. Tetrahedron Lett.
000, 41, 9879.
2
(16) (a) Ryu, I.; Fukuyama, T.; Rahman, M.; Sato, M. Synlett 2008,
151. (b) Zhang, Y.; Born, S. C.; Jensen, K. F. Org. Process Res. Dev.
2014, 18, 1476.
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Georg Thieme Verlag Stuttgart · New York — Synlett 2015, 26, 970–974