Synthesis of some carbahexopyranoses using Mn/CrCl3 mediated domino reactions and ring closing metathesis
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- 作者：Bejugam Santhosh Kumar ; Girija Prasad Mishra ; Batchu Venkateswara Rao ; venky@iict.res.in" class="auth_mail" title="E-mail the corresponding author
- 关键词：Carbasugars ; Aminocarbasugars ; Reductive elimination ; Nozaki&ndash ; Hiyama&ndash ; Kishi reaction ; Ring closing metathesis
- 刊名：Tetrahedron
- 出版年：2016
- 出版时间：14 April 2016
- 年：2016
- 卷：72
- 期：15
- 页码：1838-1849
- 全文大小：739 K
文摘
An efficient and common method for the synthesis of 5a-carba-α-d-mannopyranose 5, 5a-carba-β-d-mannopyranose 6, (+) methyl shikimate 9, (+) methyl-5-epi-shikimate 10, validamine analogue 15 and valiolamine analogue 16 from d-mannose, formal synthesis of Tamiflu 17 from d-ribose and also synthesis of 5a-carba-α-d-glucopyaranose 1, 5a-carba-β-d-glucopyaranose 2, 5a-carba-β-l-altropyranose 7 and 5a-carba-α-l-altropyranose 8 from d-xylose is described using Nozaki–Hiyama–Kishi (NHK) condition and ring closing metathesis (RCM). In this transformation 5-deoxy-5-halo-manno/ribo/xylo furanoside undergoes reductive elimination in the presence of Mn/CrCl3 to give corresponding olefin-aldehyde which was trapped by nucleophile under the same condition to afford diolefinic species which on metathesis reaction with appropriate Grubbs catalyst produced required carbocycles.