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Green Chemistry
Page 6 of 8
DOI: 10.1039/C8GC00318A
ARTICLE
Journal Name
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C. O. Tuck, E. Pérez, I. T. Horváth, R. A. Sheldon and M.
Poliakoff, Science, 2012, 337, 695.
(a) K. Barta and P. C. Ford, Acc. Chem. Res. 2014, 47, 1503;
(b) T. P. Vispute, H. Zhang, A. Sanna, R. Xiao and G. W.
Huber, Science, 2010, 330, 1222.
For selected reviews: (a) G. Guillena, D. J. Ramon and M.
Yus, Chem. Rev., 2010, 110, 1611; (b) J. F. Bower and M. J.
Krische, Top. Organomet. Chem., 2011, 34, 107; (c) A. J. A.
Watson and J. M. J. Williams, Science, 2010, 329, 635; (d) S.
Bähn, I. Sebastian, L. Neubert, M. Zhang, H. Neumann and
an imine intermediate and (ii) Ni-catalysed in situ
dehydrogenation to α-amino aldehyde followed by sequential
intramolecular C-C coupling and dehydration results
thermodynamically favourable substituted pyrroles (Scheme
2).
3
Further to elucidate the reaction pathways, imine 1c’ was
independently prepared and employed under standard
catalytic conditions. The desired pyrrole 3c was obtained in
53% yield (Scheme 8b, i and SI, Schemes S3-S7). However,
intramolecular cyclisation of intermediate 1c’ in absence of
base and catalyst, revealed their potential role (Scheme 8b, ii-
iii and SI, Scheme S5). Alternatively, control experiments using
N,N-dimethyl-ethanol with acetophenone, does not yielded
any desired product (Scheme 8c and SI, Scheme S8).
Nevertheless, to identify the possible imine intermediate 1c’, a
control experiment was carried out using β-amino alcohol 1a
with acetophenone. The reaction was interrupted after 12 h
and using 1H-NMR studies no imine intermediate was detected
(SI, Scheme S1). Thus, present experimental observations
suggests the intramolecular alkylation or cyclisation is quite
fast to detect even in NMR analysis. These mechanistic
findings are in agreement with the observation proposed by
Kempe and co-workers.9a Additionally, we observed formation
of 1-phenyl ethanol as side product derived from
acetophenone (SI, Scheme S1), support the bi-functional
activity of our nickel catalyst.17,23
M. Beller, ChemCatChem., 2011,
3, 1853; (e) G. E.
Dobereiner and R. H. Crabtree, Chem. Rev., 2010, 110, 681;
(f) C. Gunanathan and D. Milstein, Science, 2013, 341, 249.
For selected pioneering examples: (g) J. F. Bower, E. Skucas,
R. L. Patman and M. J. Krische, J. Am. Chem. Soc., 2007, 129
,
15134; (h) J. M. Ketcham, I. Shin, T. P. Montgomery and M.
J. Krische, Angew. Chem., Int. Ed., 2014, 53, 9142.
J. A. Joule, K. Mills, Heterocyclic Chemistry, 5th ed., Wiley,
Chichester, 2010.
(a) A. Hagfeldt, G. Boschloo, L. Sun, L. Kloo and H.
Pettersson, Chem. Rev., 2010, 110, 6595; (b) H. Nishide and
K. Oyaizu, Science, 2008, 319, 737.
(a) L. Knorr, Ber. Dtsch. Chem. Ges., 1884, 17, 1635; (b) C.
Paal, Ber. Dtsch. Chem. Ges., 1885, 18, 367; (c) A. Hantzsch,
Ber. Dtsch. Chem. Ges., 1890, 23, 1474; (d) S. Rakshit, F. W.
Patureau and F. Glorius, J. Am. Chem. Soc., 2010, 132, 9585;
e) Z. Chen, B. Lu, Z. Ding, K. Gao and N. Yoshikai, Org. Lett.,
2013, 15, 1966.
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5
6
7
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G. Chelucci, Coord. Chem. Rev., 2017, 331, 37.
Selected recent examples with Ru-catalysts: (a) D. Srimani,
Y. Ben-David and D. Milstein, Angew. Chem. Int. Ed., 2013,
52, 4012; Angew. Chem., 2013, 125, 4104; (b) M. Zhang, H.
Neumann and M. Beller, Angew. Chem. Int. Ed., 2013, 52
597; Angew. Chem., 2013, 125, 625; (c) M. Zhang, X. Fang,
H. Neumann and M. Beller, J. Am. Chem. Soc., 2013, 135
,
3.0 Conclusions
,
11384; (d) N. D. Schley, G. E. Dobereiner and R. H. Crabtree,
Organometallics, 2011, 30, 4174; (e) K. Iida, T. Miura, J.
Ando and S. Saito, Org. Lett., 2013, 15, 1436.
In conclusion, we have demonstrated Ni-catalysed sustainable
dehydrogenative coupling of β- and γ-amino alcohols with
ketones to access five and six member N-heterocycles. This is
the first example of such base metal catalysed pyrrole
synthesis using amino acid derived alcohols. Catalytic protocol
is highly regioselective, a variety of aryl and alkyl ketones
including nine amino alcohols having free amine, halides, alkyl,
alkoxy, alkenes, activated benzyl and pyridines smoothly
transformed into 2,3 and 2,3,5 substituted bicyclic as well as
tricyclic pyrroles, quinolines and pyridine derivatives in up to
90% yields. As a highlights, we demonstrated an interesting
pyrrole derivative employing intermolecular cyclisation of
steroid hormone with phenylalaninol.
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Selected recent examples with Ir-catalysts: (a) S. Michlik
and R. Kempe, Nat. Chem., 2013,
Obenauf, M. Friedrich, S. M. Hghne, W. Mader, G. Motz and
R. Kempe, Catal. Sci. Technol., 2014, , 4188. For a recent
5, 140; (b) D. Forberg, J.
4
example with Pt-catalyst see: (c) S. M. A. H. Siddiki, A. S.
Touchy, C. Chaudhari, K. Kon, T. Toyaoa and K. Shimizu, Org.
Chem. Front., 2016, 3, 846.
10 (a) R. M. Bullock, Catalysis Without Precious Metals, Eds.:
Wiley-VCH, Weinheim, 2010; (b) M. Albrecht, R. Bedford
and B. Plietker, Organometallics, 2014, 33, 5619; (c) I. Bauer
and H.-J. Knölker, Chem. Rev., 2015, 115, 3170; (d) B. Su, Z.-
C. Cao and Z.-J. Shi, Acc. Chem. Res., 2015, 48, 886; (e) S. J.
C. Robinson and D. M. Heinekey, Chem. Commun., 2017, 53
669.
,
11 For selected recent examples, see: (a) S. Rosler, M. Ertl, T.
Irrgang and R. Kempe, Angew. Chem. Int. Ed., 2015, 54
15046; (b) S. Elangovan. J. Neumann. J.-B. Sortais, K. Junge,
C. Darcel and M. Beller, Nat. Commun., 2016, , 12641; (c)
Conflicts of interest
,
“There are no conflicts to declare”.
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A. Mukherjee, A. Nerush, G. Leitus, L. J. W. Shimon, Y. B.
David, N. A. E. Jalapa and D. Milstein, J. Am. Chem. Soc.,
2016, 138, 4298; (d) M. Mastalir, G. Tomsu, E. Pittenauer, G.
Allmaier and K. Kirchner, Org. Lett., 2016, 18, 3462; (e) T.
Acknowledgements
The authors thank SERB, India (funding to D. B.,
ECR/2015/000600). K. S. and M. V. thank IIT-R for financial
support.
Yan, B. L. Feringa and K. Barta, Nat. Commun., 2014,
5602; (f) T. Yan, B. L. Feringa and K. Barta, ACS Catal., 2016,
, 381.
5,
6
12 For Co-catalyzed pyrrole synthesis, see: (a) P. Daw, S.
Chakraborty, J. A. Garg, Y. Ben-David and D. Milstein,
Angew. Chem. Int. Ed., 2016, 55, 14373; Angew. Chem.,
2016, 128, 14585; (b) S. P. Midya, V. G. Landge, M. K. Sahoo,
J. Rana and E. Balaraman, Chem. Commun., 2018, 54, 90.
Notes and references
6 | J. Name., 2012, 00, 1-3
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