Login Register Cart 0
Generic placeholder image

Letters in Organic Chemistry

Editor-in-Chief

ISSN (Print): 1570-1786
ISSN (Online): 1875-6255

Back
Journal Home About Journal Editorial Board Journal Insight Current Issue Volumes/Issues
Subscribe
Research Article

A Facile, Efficient and Selective Deprotection of P - Methoxy Benzyl Ethers Using Zinc (II) Trifluoromethanesulfonate

Author(s): Reddymasu Sireesha, Reddymasu Sreenivasulu, Choragudi Chandrasekhar and Mannam Subba Rao*

Volume 16, Issue 12, 2019

Page: [955 - 958] Pages: 4

DOI: 10.2174/1570178616666190222151934

Price: $65

Abstract

Deprotection is significant and conducted over mild reaction conditions, in order to restrict any more side reactions with sensitive functional groups as well as racemization or epimerization of stereo center because the protective groups are often cleaved at last stage in the synthesis. P - Methoxy benzyl (PMB) ether appears unique due to its easy introduction and removal than the other benzyl ether protecting groups. A facile, efficient and highly selective cleavage of P - methoxy benzyl ethers was reported by using 20 mole% Zinc (II) Trifluoromethanesulfonate at room temperature in acetonitrile solvent over 15-120 min. time period. To study the generality of this methodology, several PMB ethers were prepared from a variety of substrates having different protecting groups and subjected to deprotection of PMB ethers using Zn(OTf)2 in acetonitrile. In this methodology, zinc triflate cleaves only PMB ethers without affecting acid sensitivity, base sensitivity and also chiral epoxide groups.

Keywords: Facile method, PMB ethers, selective deprotection, Zn(OTf)2, acetonitrile, chiral epoxide groups.

« Previous Next »
Graphical Abstract

[1]
Greene, T.W.; Wuts, P.G.M. Protective Groups in Organic Synthesis, 2nd ed; Wiley: New York, 1991.
[2]
Kocienski, P.J. Protecting Groups; Thieme: Stuttgart, 1994.
[3]
Green, T.W.; Wuts, P.G.M. Protecting Groups in Organic Synthesis, 3rd ed; John Wileyand Sons: New York, 1999.
[4]
Greene, T.W.; Wuts, P.G.M. Protecting Groups in Organic Synthesis, 4th ed; John Wileyand Sons: New York, 2006.
[5]
Kocienski, P.J. Protecting Groups, 3rd ed; Thieme: New York, 2004.
[6]
Zweifel, G.S.; Nantz, M.H. Modern Organic Synthesis: An Introduction; W.H. Freeman: New York, 2007, p. 58.
[7]
Yu, W.; Su, M.; Gao, X.; Yang, Z.; Jin, Z. Tetrahedron Lett., 2000, 41, 4015-4017.
[8]
Srikrishna, A.; Viswajanani, R.; Sattigeri, J.A.; Vijaykumar, D. J. Org. Chem., 1995, 60, 5961-5962.
[9]
Sharma, G.V.M.; Reddy, Ch.G.; Krishna, P.R. J. Org. Chem., 2003, 68, 4574-4575.
[10]
Bartoli, G.; Dalpozzo, R.; Nino, A.D.; Maiuolo, L.; Nardi, M.; Procopio, A.; Tagarelli, A. Eur. J. Org. Chem., 2004, 2176-2180.
[11]
Bouzide, A.; Sauve, G. Lewis acid – catalyseddeprotection of p-methoxybenzyl ether. Synlett, 1997, 1153-1154.
[12]
Cappa, A.; Marcantoni, E.; Torregiani, E. J. Org. Chem., 1999, 64, 5696-5699.
[13]
Hinklin, R.J.; Kiessling, L.L. Org. Lett., 2002, 4, 1131-1133.
[14]
Hodgetts, K.J.; Wallace, T.W. Synth. Commun., 1994, 24, 1151-1155.
[15]
Onoda, T.; Shirai, R.; Iwasaki, S. Tetrahedron Lett., 1997, 38, 1443-1446.
[16]
Yan, L.; Kahne, D. Synlett, 1995, 523-524.
[17]
Weinreb, S.M.; Epling, G.A.; Comi, R.; Reitano, M. J. Org. Chem., 1975, 40, 1356-1358.
[18]
Pandey, G.; Krishna, A. Synth. Commun., 1988, 18, 2309-2314.
[19]
Fuji, K.; Ichikawa, K.; Node, M.; Fujita, E. J. Org. Chem., 1979, 44, 1661-1664.
[20]
Congreve, M.S.; Davison, E.C.; Fuhry, M.A.M.; Holmes, A.B.; Payne, A.N.; Robinson, A.; Ward, S.E. Synlett, 1993, 663-664.
[21]
Akiyama, T.; Shima, H.; Ozaki, S. Synlett, 1992, 415-416.
[22]
Hebert, N.; Beck, A.; Lennox, R.B.; Just, G. J. Org. Chem., 1992, 57, 1777-1783.
[23]
Horita, K.; Yoshioka, T.; Tanaka, T.; Oikawa, Y.; Yonemitsu, O. Tetrahedron, 1986, 42, 3021-3028.
[24]
Jung, M.E.; Koch, P. Tetrahedron Lett., 2011, 52, 6051-6054.
[25]
Tucker, J.W.; Narayanam, J.M.R.; Shah, P.S.; Stephenson, C.R.J. Chem. Commun. , 2011, 47, 5040-5042.
[26]
Bhatt, V.P.; Samant, S.D.; Pednekar, S. Synth. Commun., 2017, 47, 968-974.
[27]
Ravikumar, K.S.; Chandrasekaran, S. J. Org. Chem., 1996, 61, 826-830.
[28]
Sharma, G.V.M.; Reddy, Ch.G.; Krishna, P.R. J. Org. Chem., 2003, 68, 4574-4575.
[29]
Poornima, B.; Venkanna, A.; Swetha, B.; Kamireddy, K.R.; Siva, B.; Babu, V.S.P.; Ummanni, R.; Babu, K.S. Tetrahedron, 2016, 72, 4789-4797.

Rights & Permissions Print Cite
Article Metrics
52
3
1
© 2024 Bentham Science Publishers | Privacy Policy