硫(IV)化合物作为配体:XX。噻吩-1-氧化物与有机锡卤化物的加合物形成和开环。的晶体结构[(4- FC 6 H ^ 4)2的SnCl 2(C 2 H ^ 4 SO)2 ]
摘要:
有机锡卤化物R n SnX 4- n(RPh,4-MeC 6 H 4,4 -FC 6 H 4 ; X Br Cl,Br; n = 0,1,2,3)和Me 2 SnCl 2形成与1,1-氧杂硫杂环丁烷加成。通常,对于n = 0、1、2,它们的化学计量比为1:2,并且是八面体的,如[(4-FC 6 H 4)2 SnCl 2(C 2 H 4 SO )的单晶结构研究所示。)2 ](4c)。在4c中,芳基是彼此互反,氯化物和亚砜配体互相顺。SO键比未配位的噻吩-1-氧化物中的键长0.04Å,而三元环中的键缩短了相似的量。取决于反应条件,可以有1:1的加合物[R 2 SnX 2(C 2 H 4 SO)](R = 4-MeC 6 H 4,XCl,Br; RMe,t也可以分离Bu,XCl),而三有机锡卤化物仅形成1:1的复合物。已经合成了类似的二甲基亚砜(DMSO)加合物用于比较。根据振动光谱数
Direct CâH bond arylation of simple arenes with aryltin reagents has been successfully catalysed by PdCl2 in the presence of CuCl2. CuCl2 proved to be an activator for a palladium intermediate as well as an oxidant.
obtained suggest that the transmission of electroniceffects from one aromatic ring to another in compounds of the type Ar4Sn occurs mainly by an inductive mechanism. In conjunction with the data on similar systems containing other bridging atoms, the results obtained provide a quantitative measure of the relative ability of tin-aromatic carbon bonds to transmit electroniceffects.
Reagents containing carbon–tin–halogen inter-element linkages were effective for palladium-catalyzed carbostannylation. In situ generated allyltin trichlorides add to carbon–carbondoublebonds of bicyclo[2.2.1]hept-2-ene (norbornene) and bicyclo[2.2.1]hepta-2,5-diene (norbornadiene), stereoselectively, under the catalysis of palladium(0) species in good yields. The regioselectivity of unsymmetrically
Stille Cross-Couplings of Unactivated Secondary Alkyl Halides Using Monoorganotin Reagents
作者:David A. Powell、Toshihide Maki、Gregory C. Fu
DOI:10.1021/ja0436300
日期:2005.1.1
The first catalyst that achieves Stille cross-couplings of secondary (as well as primary) alkyl halides has been developed. The method employs easily handled and inexpensive catalyst components (NiCl2 and 2,2'-bipyridine) and, through the use of monoorganotin reagents, avoids the formation of toxic and difficult-to-remove triorganotin side products.