A Sequential Homologation of Alkynes and Aldehydes for Chain Elongation with Optional <sup>13</sup>
C-Labeling
作者:Andreas Brunner、Lukas Hintermann
DOI:10.1002/chem.201504248
日期:2016.2.18
Terminal alkynes (RCCH) are homologated by a sequence of ruthenium‐catalyzed anti‐Markovnikov hydration of alkyne to aldehyde (RCH2CHO), followed by Bestmann–Ohira alkynylation of aldehyde to chain‐elongated alkyne (RCH2CCH). Inverting the sequence by starting from aldehyde brings about the reciprocal homologation of aldehydes instead. The use of 13C‐labeled Bestmann–Ohira reagent (dimethyl ((1‐13
末端炔烃(RCCH)通过一系列钌催化的炔烃反Markovnikov水合反应成醛(RCH 2 CHO)进行同源化,然后将醛的Bestmann-Ohira炔基化反应成链延长的炔烃(RCH 2 CCH)。通过从醛开始来反转序列反而导致了醛的相互同源。使用13 C标记的Bestmann-大平试剂(二甲基((1- 13 C)-1-重氮基-2-氧代丙基)膦酸酯),用于提供炔基直接的访问单独使用或通过附加的同系化,乘以13 C标记的炔烃。标记的炔烃用作合成平台,可访问大量特定的13种C标签产品。炔烃单元中带有一个或两个13 C标签的末端炔烃已提交给炔-叠氮化物点击反应;如13 C NMR光谱分析所示,发现铜催化型(CuAAC)在1,5-三嗪异构体上对1,4的区域选择性> 500 000:1 。