芳香族硫化合物的两个新的钯催化反应使二苯并噻吩在四个步骤中转化为苯并菲。一种芳族骨架向另一种芳族骨架的转化包括:1)二苯并噻吩的4-氯丁基化反应形成相应的sulf盐; 2)钯盐与四芳基硼酸钠的钯催化的芳基开环反应; 3)分子内S N 2反应以形成teraryl锍盐,和4)的钯催化的分子内ç S / C H至电palladation耦合。以量身定制的方式合成了所需的对称和不对称的三亚苯基,其总收率令人满意。
2-mercapto-2‘-substituted-1,1‘-biphenyls (8a−c) and 2-mercapto-2‘-substituted-1,1‘-binaphthyls (8d) in high yields. The mercapto group in the axiallychiralcross-coupling products was converted into several functional groups by way of the methylsulfinyl group. The rate of flipping in dinaphthothiophene was measured by variable-temperature 31P NMR analysis of methylphenylphosphinyldinaphthothiophene derivative (21)
1,9-二取代的二苯并噻吩(6a - c)和二萘并噻吩(6d)与芳基和烷基格利雅试剂(7)的催化不对称格利雅交叉反应在存在a的情况下以高对映选择性(高达ee的95%)进行在THF中与2-二苯基膦-1,1'-联萘基(H-MOP)或恶唑啉-膦配体(i -Pr-phox)配位的镍催化剂(3-6 mol%)得到2-巯基-2'-取代的-1,1'-联苯(8a - c)和2-巯基-2'-取代的1,1'-联萘基(8d)高产。轴向手性交叉偶联产物中的巯基通过甲基亚磺酰基基团转化为几个官能团。通过对甲基苯基膦基二萘并噻吩衍生物(21)的可变温度31 P NMR分析来测量二萘并噻吩的翻转速率。
Thiolate-Initiated Synthesis of Dibenzothiophenes from 2,2′-Bis(methylthio)-1,1′-Biaryl Derivatives through Cleavage of Two Carbon–Sulfur Bonds
A catalytic reaction involving the cleavage of two carbon–sulfurbonds in 2,2′-bis(methylthio)-1,1′-biaryl derivatives is reported. This reaction does not require a transition-metal catalyst and is promoted by a thiolate anion. Notably, based on DFT calculations, the product-forming cyclization step is shown to proceed through a concerted nucleophilic aromatic substitution (CSNAr) mechanism.
A palladium-catalyzed synthesis of dibenzothiophenes from 2-biphenylthiols is described. This highly efficient reaction employs a simple PdCl2/DMSO catalytic system, in which PdCl2 is the sole metal catalyst and DMSO functions as an oxidant and solvent. This transformation has broad substrate scope and operational simplicity and proceeds in high yield. The synthetic utility was demonstrated by the
The FVP method of ethynyl and chlorovinyl materials is applied to the ready formation of sulfur-containing fused heteroaromatic systems. The pyrolysis of the chlorovinyl materials is assumed to involve a mechanism different from that of the ethynyl materials.
Opening and Hydrogenation of Dinaphtho[2,1-<i>b</i>:1‘,2‘-<i>d</i>]thiophene (DNT) by Soluble Rhodium and Iridium Complexes. Homogeneous Hydrogenolysis of DNT to 1,1‘-Binaphthalene-2-thiol by Rhodium Catalysis
with protic acids. The complex (triphos)RhH3 (6) reacts with DNT (THF, 70 °C) to give exclusively the dihydride thiolate product (triphos)Rh(H)2(SC20H13). The latter complex reacts in THF with KOBut in the presence of H2 (5 atm) at room temperature to give the trihydride 6 and potassium 1,1‘-binaphthalene-2-thiolate. In the presence of a strong base (KOBut), the π-alkyne complex [(triphos)Rh(η2-MeO2CC⋮CCO2Me)]PF6