Sensitized photo-oxygenation of a wide variety of acyclic 1,3-dienes was investigated. The 1,4-cycloaddition of singlet oxygen to acyclic conjugated dienes was closely related to the thermal Diels-Alder reaction in stereospecificity, and steric and electronic effects of substituents. Reactivity order of singlet oxygen toward conjugated dienes and isolated C—C double bonds was exhibited as follows:
Preparation and reactivity of dinuclear RuII complexes with bridging thiolate ligands [Cp★Ru(μ-SR)2RuCp★] (Cp★ η5-C5Me5; R iPr, tBu, 2,6-Me2C6H3).Oxidative addition of alkyl halides at the diruthenium center
fluxional nature of complexes3 in solution resulting from the Ru2S2 ring inversion. Complex 3a (R iPr) underwent oxidative addition of RX (R PhCH2CH2 or PhCH2, X Br; R Me or Et, X I) and H2 across the Ru2 center to give [Cp★RuR(μ-SiPr)2RuCp★X] (7) and [Cp★RuH(μ-SiPr)2RuCp★H], respectively. The structure of 7a (R PhCH2CH2, X Br) has been determined by X-ray crystallography. Crystal data for 3c:
的[Cp★的RuCl]的反应4(CP★η 5 -C 5我5)与纳斯尔(R我PR,吨卜,2,6--ME 2 ç 6 ħ 3)在THF双核,得到钌II络合物与两个桥接硫醇盐配体[Cp★Ru(μ-SR)2 RuCp★](3)。X射线分析3c(R = 2,6-Me 2 C 6 H 3)揭示了具有两个赤道C 6 H 3 Me 2的折叠Ru 2 S 2芯结构。固态有-2,6个基团,而1 H NMR可变温度研究的结果可诊断因Ru 2 S 2环反转而形成的络合物3在溶液中的通量性质。复杂的图3a(R我PR)后行氧化加成RX的(R的PhCH 2 CH 2或物理信道2,X溴; RMe或Et,XI)和H 2穿过的Ru 2中心,得到的[Cp ★RUR(μ-S我PR)2 RuCp★X](7)和的[Cp★期RuH(μ-S我PR)2 RuCp★H],分别。的结构图7a(R的PhCH 2 CH 2,X溴