林文偉李玉婷2019-09-042017-6-182019-09-042012http://etds.lib.ntnu.edu.tw/cgi-bin/gs32/gsweb.cgi?o=dstdcdr&s=id=%22GN0698420070%22.&%22.id.&http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/100840苯并呋喃衍生物在有機合成中為一重要的研究領域，運用本實驗室過去合成呋喃的核心概念以有效合成苯并呋喃分子。反應機構推測為三丁基磷先與醛類或 Michael 受體進行1,2或1,4-加成反應，接著進行氧-醯化和去質子化，最後經由分子內 Wittig 合環反應，即可獲得苯并呋喃產物，產率介於27-98 %。我們可分離出重要中間體109，且證明其可經由分子內 Wittig 合環反應，而獲得苯并呋喃分子。另外，ylide中間體118分子上具有兩個酯基，反應具有化學選擇性的進行分子內 Wittig 反應，我們可調控不同的醯氯，來控制反應的化學選擇性，而可生成苯并呋喃或呋喃分子。Benzofurans were of great importance in organic chemistry. In this part, they can be efficiently synthesized according to our developed protocol. The reaction mechanism is proposed to undergo the 1,2- or 1,4-addition reactions of PBu3 toward aldehydes or Michael acceptors followed by acylation, deprotonation and finally intramolecular Wittig reactions to furnish benzofurans in 27-98% yields. The phosphonium chlorides as the key intermediates could also be isolated and further converted into the products via intramolecular Wittig reactions. Furthermore, the phosphorus ylide with two ester groups such as 118 could undergo chemoselective intramolecular Wittig reactions to provide the corresponding furans or benzofurans. Various interesting products could be prepared via tunable chemoselective intramolecular Wittig reaction by using the suitable acylating reagents.Wittig 反應苯并呋喃Wittig reactionbenzofuran