Synthesis and Stability of a Homologous Series of Triynol Natural Products and Their Analogues
摘要:
A series of polyyne natural products 1, 13, and 31 and analogues 14, 21, and 22 are synthesized in six steps. The key step is a Fritsch-Buttenberg-Wiechell rearrangement in which a triyne framework is formed from the appropriate dibromoolefin precursor. Terminal conjugated triynes 13 and 14 are obtained as highly unstable products that rapidly decompose under ambient conditions. The stability of triynols increases via either the addition of methylene units (i.e., 6 -> 31 -> 1) or addition of terminal substituents (i.e., 13 -> 21 or 31).
One-Pot Formation and Derivatization of Di- and Triynes Based on the Fritsch−Buttenberg−Wiechell Rearrangement
作者:Thanh Luu、Yasuhiro Morisaki、Nina Cunningham、Rik R. Tykwinski
DOI:10.1021/jo701810g
日期:2007.12.1
A divergent, one-pot synthesis of functionalized polyynes has been developed. Beginning with the appropriately substituted dibromoolefinic precursor, a carbenoid Fritsch−Buttenberg−Wiechell (FBW) rearrangement is used to generate the lithium acetylide of a conjugated polyyne framework, and subsequent trapping with carbon-based electrophiles provides for in situ formation of a wide range of di- and
One-Pot Synthesis and Functionalization of Polyynes via Alkylidene Carbenoids
作者:Rik Tykwinski、Thanh Luu、Yasuhiro Morisaki
DOI:10.1055/s-2007-1000937
日期:——
one-pot, two-step method for the synthesis of diynes and triynes is reported. The reaction of a dibromoolefinic precursor with BuLi effects a Fritsch-Buttenberg-Wiechell rearrangement and generates a lithium acetylide intermediate, which is then trapped with a variety of electrophiles to produce substituted diynes and triynes. Alternatively, transmetalation from the lithium acetylide to give a zinc acetylide