Application of directed metallation in synthesis. Part 3: Studies in the synthesis of (±)-semivioxanthin and its analogues
摘要:
The synthesis of several analogues of (+/-)-semivioxanthin including five thiophene analogues, using directed metalation are reported. The strategy consisted of the synthesis of functionalized naphthalene or benzo[b]thiophene as building blocks followed by annelation of the pyrone. (C) 2003 Elsevier Science Ltd. All rights reserved.
Directed ortho metalation of n,n-diethyl benzamides. Methodology and regiospecific synthesis of useful contiguously tri- and tetra-substituted oxygenated aromatics, phthalides and phthalic anhydrides
作者:S.O. de Silva、J.N. Reed、R.J. Billedeau、X. Wang、D.J. Norris、V. Snieckus
DOI:10.1016/s0040-4020(01)81579-9
日期:1992.6
contiguously 1,2,3- and 1,2,3,4-substituted benzamides (Tables 2) are given. The efficient conversion of these benzamides (6, 10, 12, 13, 18, 19) into phthalides (9a–b, 16b–c, 17) and phthalic anhydrides (8, 16a), compounds previously available by demanding, classical methods, is detailed. A short synthesis of iso-ochracinic acid (27) is described.
Directed <i>ortho</i>
-Metalation of Aryl Amides, <i>O-</i>
Carbamates, and Methoxymethoxy Systems: Directed Metalation Group Competition and Cooperation
作者:M. A. Jalil Miah、Mukund P. Sibi、S. Chattopadhyay、Oluwole B. Familoni、Victor Snieckus
DOI:10.1002/ejoc.201701143
日期:2018.1.31
metalation-electrophile quench of 1,2- and 1,4-O-carbamates (Scheme 2) and iterative metalation procedures (Scheme 3) is presented. The results provide new methodology for the synthesis of functionalized contiguously 1,2,3- and 1,2,3,4-substituted aromatic derivatives of difficult accessibility and potential broad utility. A comparison of the present methodology with previously developed routes is given in selected