Synthesis of Amido-N-imidazolium Salts and their Applications as Ligands in Suzuki-Miyaura Reactions: Coupling of Hetero- aromatic Halides and the Synthesis of Milrinone and Irbesartan
作者:Manian Rajesh Kumar、Kyungho Park、Sunwoo Lee
DOI:10.1002/adsc.201000592
日期:2010.12.17
catalytic system based on palladium-amido-N-heterocyclic carbenes for Suzuki–Miyauracouplingreactions of heteroaryl bromides is described. A variety of sterically bulky, amido-N-imidazoliumsalts were synthesized in high yields from the corresponding anilines. This catalytic system effectively promoted Suzuki–Miyauracouplings of heteroaryl bromides and chlorides with a range of boronic acids to
Cross-Coupling of Triallyl(aryl)silanes with Aryl Bromides and Chlorides: An Alternative Convenient Biaryl Synthesis
作者:Akhila K. Sahoo、Takuro Oda、Yoshiaki Nakao、Tamejiro Hiyama
DOI:10.1002/adsc.200404188
日期:2004.12
give various biaryls in good yields. It is worthwhile to note that the all-carbon-substituted arylsilanes, stable towards moisture, acid, and base and easily accessible, serve as a highly practical alternative to their aryl(halo)silane counterparts. A catalyst system consisting of [(η3-C3H5)PdCl]2 and 2-[2,4,6-(i-Pr)3C6H2]-C6H4PCy2 and use of TBAF⋅3 H2O in THF-H2O are effective especially for the cross-coupling
在DMSO-H 2 O中存在PdCl 2 / PCy 3和氟化四丁基铵(TBAF)的情况下,多种芳基溴化物与三烯丙基(芳基)硅烷的交叉偶联是有效的,以高收率得到各种联芳基。值得一提的是,全碳取代的芳基硅烷对水分,酸和碱稳定,易于获得,可作为其芳基(卤代)硅烷对应物的高度实用替代品。由[(η的催化剂体系3 -C 3 H ^ 5)的PdCl] 2和2- [2,4,6-(我-Pr)3 c ^ 6 ħ 2 ] -C 6 H ^ 4 PCY2和在THF-H 2 O中使用TBAF·3 H 2 O对于与芳基氯的交叉偶联特别有效。两种催化剂体系均能耐受多种常见的官能团。推测反应的高效率归因于用TBAF·3 H 2 O和适量的水处理后烯丙基的易裂解。二烯丙基(二苯基)硅烷还可以与各种芳基溴化物和氯化物交联,收率很高,而烯丙基(三苯基)硅烷只能以中等收率得到交联产物。通过溴氯苯与不同芳基硅烷的顺序交叉偶联,可
Accessing Difluoromethylated and Trifluoromethylated
<i>cis</i>
‐Cycloalkanes and Saturated Heterocycles: Preferential Hydrogen Addition to the Substitution Sites for Dearomatization
作者:Xue Zhang、Liang Ling、Meiming Luo、Xiaoming Zeng
DOI:10.1002/anie.201907457
日期:2019.11.18
Reported here is a straightforward process in which a cyclic (alkyl)(amino)carbene/Rh catalyst system facilitates the preferential addition of hydrogen to the substitutionsites of difluoromethylated and trifluoromethylated arenes and heteroarenes, leading to dearomative reduction. This strategy enables the diastereoselective synthesis of cis-difluoromethylated and cis-trifluoromethylated cycloalkanes
[EN] A NEW METHOD OF 18F LABELLING AND INTERMEDIATE SALTS<br/>[FR] NOUVEAU PROCÉDÉ D'ÉTIQUETAGE DE 18F ET DE SELS INTERMÉDIAIRES
申请人:NAT UNIV SINGAPORE
公开号:WO2021126080A1
公开(公告)日:2021-06-24
Disclosed herein is a salt of formula I: where R1, X, n, R, R1, Y, m, p, q, Z and o are as defined herein. Also disclosed herein are methods of using said salts in chemical synthesis, such as to prepare compounds isotopically enriched in 18F for use in PET imaging, as well as methods to make the compounds of formula I.
Frustrated Lewis-Pair-Meditated Selective Single Fluoride Substitution in Trifluoromethyl Groups
作者:Dipendu Mandal、Richa Gupta、Amit K. Jaiswal、Rowan D. Young
DOI:10.1021/jacs.9b12167
日期:2020.2.5
developed a generic protocol that allows a single substitution of one fluoride in trifluoromethylgroups with neutral phosphine and pyridine bases. The resulting phosphonium and pyridinium salts can be further functionalized via nucleophilic substitution, photoredox coupling and electrophilic transfer reactions allowing the generation of a vast array of difluoromethyl products.