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Organic & Biomolecular Chemistry
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Chemical Science
ARTICLE
9
factors. Equally importantly, we hope that the present study
will provide guidance for THP synthesis as well.
6179.
DOI: 10.1039/C9OB00750D
10 S. L. Schreiber, Science 2000, 287, 1964-1969.
11 For an example of the C2 opening of styrene oxide, see G.
M. Whitesides, J. D. Roberts, J. Am. Chem. Soc. 1965, 87,
4878-4888.
12 We have previously shown that TBS deprotection and oxa-
Michael addition can occur in tandem fashion under these
conditions, see refs 3a, c and f.
Conflicts of interest
There are no conflicts to declare.
13 N. Greeves, W.-M. Lee, Tetrahedron Lett. 1997, 38, 6445-
6448.
Acknowledgements
14 E. K. Starosin, D. B. Furman, A. V. Ignatenko, A. P. Barkova,
G. I. Nikishin, Russ. Chem. Bull. 2006, 55, 2016-2019.
15 Details have been deposited with the Cambridge
Crystallographic Data Centre and may be obtained at
trans-19 1895903; cis-20 1895904; trans-21 1895902.
16 We also examined hexamethyldisilazide bases, but we
obtained erratic results. This is likely to be due to
aggregation of these bases: R. E. Mulvey, S. D. Robertson,
Angew. Chem. Int. Ed. 2013, 52, 11470-11487.
RR thanks IISER Tirupati, and SERB, DST, Govt. of India for the
Early Career Research Award (ECR/2016/000041); DC, AHXY
and RWB thank Pfizer and Nanyang Technological University
for generous support of this work; AHXY thanks the
Economic Development Board and Pfizer for an EDB IPP
Scholarship. We thank Dr. Li Yongxin and Dr. Rakesh Ganguli
(NTU) for determination of the X-Ray structures.
17 It is possible that the basicity of the alkoxides is enhanced
by the sequestration of the counter cation by the crown
ether, so the increased proportion of cis isomer may be
due to equilibration.
18 We also found the behaviour of this base to be capricious.
Commercial material was inactive, while material
prepared in our own laboratory had to be used promptly.
19 We have previously observed this effect in a different
context: R. W. Bates, C. J. Gabel, J. Ji, T. Rama-Devi,
Tetrahedron, 1995, 51, 8199-8212.
Notes and references
1
For reviews of intramolecular oxa-Michael addition, see (a)
J. Hu, M. Bian, H. Ding, Tetrahedron Lett. 2016, 57, 5519-
5539; (b) N. M. Nasir, K. Ermanis, P. A. Clarke, Org. Biomol.
Chem. 2012, 12, 3323-3335 (c) H. Fuwa, Heterocycles 2012,
86, 1255-1298; (d) C. F. Nising, S. Bräse, Chem. Soc. Rev.
2012, 41, 988-999; (e) I. Larossa, P. Romea, F. Urpí,
Tetrahedron 2008, 64, 2683-2723; (f) P. A. Clarke, S.
Santos, Eur. J. Org. Chem. 2006, 2045-2053.
(a) A. Gómez-Palomino, M. Pellicena, K. Krämer, P. Romea,
F. Urpí, G. Aullón, J. M. Padrón, Org. Biomol. Chem. 2017,
15, 1842-1862; (b) L. Yang, Z. Lin, S.-H. Huang, R. Hong,
Angew. Chem., Int. Ed. 2016, 55, 6280-6284; (c) S. J.
Gharpure, J. V. K. Prasad, K. Bera, Eur. J. Org. Chem. 2014,
3570-3574; (d) I. Paterson, G. W. Haslett, Org. Lett. 2013,
15, 1338-1341; (e) S. Takahashi, Y. Akita, T. Nakamura, H.
Koshino, Tet. Asymmetry 2012, 23, 952-958; (f) H. Fuwa, N.
Ichinokawa, K. Noto, M. Sasaki, J. Org. Chem. 2012, 77,
2588-2607; (g) C. Bressy, F. Allais, J. Cossy, Synlett 2006,
3455-3456; (h) A. Bhattacharjee, O. Soltani, J. K. De
Brabander, Org. Lett. 2002, 4, 481-484; (i) C. Schneider, A.
Schuffenhauer, Eur. J. Org. Chem. 2000, 73-82; (j) S. V. Ley,
D. S. Brown, J. A. Clase, A. J. Fairbanks, I. C. Lennon, H. M.
I. Osborn, E. S. E. Stokes, D. J. Wadsworth, J. Chem. Soc.,
Perkin Trans. 1 1998, 2259-2276; (k) M. G. Banwell, C. T.
Bui, H. T. T. Pham, G. W. Simpson, J. Chem. Soc., Perkin
Trans. 1 1996, 967-969. For a comprehensive listing and
discussion, see the S.I.
20 Note: where two conformers are likely to be of
significance, only one is shown for clarity.
2
21 MacroModel; Schrödinger, LLC: New York, NY, 2016.
22 M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M.
A. Robb, J. R. Cheeseman, G. Scalmani, V. Barone, B.
Mennucci, G. A. Petersson, H. Nakatsuji, M. Caricato, X. Li,
H. P. Hratchian, A. F. Izmaylov, J. Bloino, G. Zheng, J. L.
Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J.
Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H.
Nakai, T. Vreven, J. A. Montgomery Jr., J. E. Peralta, F.
Ogliaro, M. Bearpark, J. J. Heyd, E. Brothers, K. N. Kudin, V.
N. Staroverov, R. Kobayashi, J. Normand, K. Raghavachari,
A. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi, N.
Rega, J. M. Millam, M. Klene, J. E. Knox, J. B. Cross, V.
Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R. E.
Stratmann, O. Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J.
W. Ochterski, R. L. Martin, K. Morokuma, V. G. Zakrzewski,
G. A. Voth, P. Salvador, J. J. Dannenberg, S. Dapprich, A. D.
Daniels, Ö. Farkas, J. B. Foresman, J. V. Ortiz, J. Cioslowski,
D. J. Fox, Gaussian 09, Revision E.01; Gaussian, Inc.:
Wallingford CT, 2009.
23 (a) J.-D. Chai, M. Head-Gordon, Phys. Chem. Chem. Phys.
2008, 10, 6615−6620. (b) J.-D. Chai, M. Head-Gordon, J.
Chem. Phys. 2008, 128, 084106.
24 A. V. Marenich, C. J. Cramer, D. G. Truhlar, J. Phys. Chem. B
2009, 113, 6378−6396.
25 C. Y. Legault, CYLview, 1.0b; Université de Sherbrooke,
26 As all acids appear to give the same stereochemical
outcome, the role of the counter ion was disregarded.
27 See the S.I. for the definition of pyramidalisation.
28 The importance of the Bürgi-Dunitz angle in intramolecular
cyclisations has been questioned: C. I. Bayly, F. Grein, Can.
J. Chem. 1989, 67, 2173-2177.
29 We thank a reviewer for the suggestion of repulsion
between the oxygen atoms.
30 D. H. R. Barton Experientia 1950, VI/8, 316.
3
(a) R. W. Bates, P. Song, Tetrahedron, 2007, 63, 4497-4499;
(b) R. W. Bates, K. Palani, Tetrahedron Lett., 2008, 49,
2832-2834; (c) R. W. Bates, P. Song, Synthesis, 2010, 2935-
2942; (d) R. W. Bates, T. G. Lek, Synthesis 2014, 1731-1738;
(e) R. W. Bates, L. Li; K. Palani; W. Phetsang, J. K. Loh, Asian
J. Org. Chem. 2014, 7, 792-796; (f) R. W. Bates, K. Wang, G.
Zhou, D. Z. Kang, Synlett 2015, 751-754; (g) D. Csókás, R.
W. Bates, Synlett 2019, 30, 178-180.
4
5
For an example, see ref 2h.
M. A. Ramírez, J. M. Padrón, J. M. Palazón, V. S. Martín, J.
Org. Chem. 1997, 62, 4584-4590.
6
7
8
O. Yonemitsu, T. Yamazaki, J.-i. Uenishi, Heterocycles 1998,
49, 89-92.
R. Takagi, H. Nishitani, S. Takenami, K. Okada, S. Kojima, K.
Ohkata, Bull. Chem. Soc. Jpn. 2001, 74, 1901-1907.
K. Ermanis, Y.-T. Hsiao, U. Kaya, A. Jeuken, P. A. Clarke,
Chem. Sci. 2017, 8, 482-490.
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