A Versatile Route to 3-Benzoheteroepines Containing Group 15 and 16 Heavier Elements Involving Several Novel Ring Systems, and Their Thermal Stabilities
The C-unsubstituted 3-benzoheteroepines (2a-g) containing group 15 (P, As, Sb, and Bi) and group 16 (S, Se, and Te) heavier elements were prepared by the reaction of the corresponding metal reagents with (Z,Z)-o-bis(beta-lithiovinyl)benzene (5) which was derived in two steps from a common o-phthalaldehyde (3). The heteroepines (2) thus obtained were thermally labile towards heteroatom extrusion, and
Double Transfer of Chirality in Organocopper-Mediated bis(Alkylating) Cycloisomerization of Enediynes
作者:Damien Campolo、Tanzeel Arif、Cyril Borie、Dominique Mouysset、Nicolas Vanthuyne、Jean-Valère Naubron、Michèle P. Bertrand、Malek Nechab
DOI:10.1002/anie.201310530
日期:2014.3.17
An original synthesis of chiral benzofulvenes triggered by organocopper reagents is reported. These enantiopure products are available through a highly chemo‐, regio‐, diastereo‐, and enantioselective bis(alkylating) cycloisomerization process. A doublechiralitytransfer (central‐to‐axial‐to‐central) is observed.
Triynes having a phenylene‐bridged 1,5‐diyne moiety were transformed into substituted tetraphenylenes by the title sequence. A cationic Rh–ligand species catalyzed this highly enantioselective reaction. This protocol is a new and easy approach to the construction of the tetraphenylene skeleton and enables an efficient asymmetric synthesis (see scheme; R=H; Z=NTs, C(CO2Me)2, O).
具有亚苯基桥接的1,5-二炔部分的三炔通过标题序列转化为取代的四亚苯基。阳离子Rh-配体物种催化了这种高度对映选择性的反应。该协议是一种构造四亚苯基骨架的新方法,可轻松实现高效的不对称合成(请参见方案; R = H; Z = NTs,C(CO 2 Me)2,O)。
Triflic Acid Mediated Cascade Cyclization of Aryldiynes for the Synthesis of Indeno[1,2-<i>c</i>]chromenes: Application to Dye-Sensitized Solar Cells
A new triflicacid (TfOH)‐mediatedcascadecyclization of ortho‐anisole‐substituted aryldiynes is described for the construction of indeno[1,2‐c]chromenes. The cascadecyclization proceeds through an unusual TfOH‐induced alkyne‐alkyne cyclization followed by nucleophilic attack of the methoxy group on the benzylidene cation, which is completely different to the cyclization of ortho‐aniline‐ or ort
描述了一种新的由三氟甲磺酸(TfOH)介导的邻苯甲醚取代的芳基二炔的级联环化反应,用于构建茚并[1,2- c ]苯二酮。级联环化是通过不寻常的TfOH诱导的炔烃-炔烃环化进行的,随后甲氧基对苄叉基阳离子的亲核攻击,这与邻苯胺或邻苯硫基苯甲醚取代的芳基二炔的环化完全不同。合成了以茚并[1,2- c ]亚甲基骨架为供体和π-连接基的一类新型有机染料。这些化合物在染料敏化太阳能电池(DSC)中表现出很高的光伏性能。
Catalytic Generation of Arynes and Trapping by Nucleophilic Addition and Iodination
A fair exchange: In the title reaction, alkynyllithium serves as an initiator for benzyne generation through an iodine–lithium exchange (see scheme; Tf=trifluoromethanesulfonyl). When performed in the presence of stoichiometric amounts of a nucleophile, the generated benzyne undergoes attack by lithio nucleophiles to generate aryllithium, which is then iodinated by iodoalkyne to give the iodoarenes