Direct synthesis of anthracenes from o-tolualdehydes and aryl iodides through Pd(II)-Catalyzed sp C H arylation and electrophilic aromatic cyclization
作者:Hyojin Park、Kwangho Yoo、Byunghyuck Jung、Min Kim
DOI:10.1016/j.tet.2018.03.006
日期:2018.4
The first direct synthesis of substituted anthracenes from o-tolualdehydes and aryl iodides via a Pd(II)-catalyzed CH arylation using an alcohol-bearing transient directing group and subsequent AgOTf-assisted electrophilic aromatic cyclization is described. New transient directing groups consisting of amino acids and amino alcohols enhanced the reactivity, and the CH arylation was complete in 12 h
Acetohydrazone: A Transient Directing Group for Arylation of Unactivated C(sp<sup>3</sup>)–H Bonds
作者:Fei Ma、Min Lei、Lihong Hu
DOI:10.1021/acs.orglett.6b01170
日期:2016.6.3
A straightforward and efficient method has been developed for the synthesis of 2-benzylbenzaldehyde derivatives from 2-methylbenzaldehyde and iodobenzene via a C(sp3)–H activation process. In the course of the activation reaction, acetohydrazone is formed between 2-benzylbenzaldehyde and acetohydrazine as a transient directing group. As a new kind of transient directing group, acetohydrazone exhibits
Semicarbazide: A Transient Directing Group for C(
<i>sp</i>
<sup>3</sup>
)−H Arylation of 2‐Methylbenzaldehydes
作者:Fei Wen、Zheng Li
DOI:10.1002/adsc.201901392
日期:2020.1.7
Semicarbazide as an effective transientdirectinggroup for C(sp3)−Harylation of 2‐methylbenzaldehydes is described. Various substituted 2‐benzylbenzaldehydes are efficiently synthesized by this strategy. The salient features of this protocol are the use of inexpensive transientdirectinggroup, wide scope of substrates with good functional group compatibility, up to 98% yield, and applicability to
Polycyclic aromatic compounds can be synthesized from 2-benzylic- or 2-allylbenzaldehydes using a catalytic amount of In(III) or Re(I) complexes. By using this method, polycyclic aza-aromatic compounds can also be prepared efficiently. In these reactions, only water is formed as a side product.