Catalytic Cleavage of Carbon Unreactive Bonds by the Coordination of a Directing Group

(1)研究了N-2-吡啶基烷基胺中与氮原子相邻的sp3C-H键断裂的催化反应。以Ru_3(CO)_12&gt；为催化剂，在烯烃键上加成了sp3c-H键，得到了偶联产物。包括端烯、内烯和环烯在内的各种烯烃可用于偶联反应。在Ru_3(CO)_2和HCOONH_4存在下，吡啶酯与HCOONH_4发生脱羰基还原生成烃类化合物。使用有机硼化合物作为偶联对导致交叉偶联反应生成酮，并且没有发生脱羰基反应。氢化硅烷也可以用来代替HCOONH_4作为还原剂。对于这两个反应，各种官能团都是相容的。两个CATAL…的关键一步更多的裂解反应是基团促进的酯基碳氧键的直接断裂，导致了酰基过渡金属烷氧基配合物的生成。(3)在Ru或Re配合物的催化下，实现了N-苯基吡唑苯环上C-H键的直接羰化反应。N-苯基吡唑与一氧化碳和乙烯在Ru_3(CO)_(12)或Rh_4(CO)_(12)和Rh_4(CO)_(12&gt)存在下的反应导致苯环上的邻位C-H键的位置选择性羰基化反应，得到相应的乙酮。苯环上的各种官能团是可以容忍的。基于吡唑共轭酸的pKa值，N-苯基吡唑具有比预期更高的反应活性。反应的溶剂选择很重要，其中N，N-二甲基乙酰胺(DMA)的反应效果最好。(4)在Rh_4(CO)_2和CO的存在下，烯烃与吡啶甲醇和CO的反应在较温和的条件下发生了氢酯化反应。用苯甲醇代替吡啶乙醇无反应。较少

(1)Catalytic reactions which involve the cleavage of an sp^3 C-H bond adjacent to a nitrogen atom in N-2-pyridynyl alkylamines are explored. The use of Ru_3(CO)_<12> as the catalyst results in the addition of the sp^3C-H bond across alkene bond to give the coupling products. A variety of alkenes, including terminal, internal, and cyclic alkenes, can be used for the coupling reaction. The presence of directing groups, such as pyridine, pyrimidine, and an oxazoline ring, on the nitrogen of the amine is critical for a successful reaction.(2)The reaction of pyrydinyl esters with HCOONH_4 in the presence of Ru_3(CO)_<12> resulted in decarbonylative reduction to give hydrocarbons. The use of organoboron compounds as a coupling partner resulted in cross-coupling reaction to give ketones, and no decarbonylation took place. A hydrosilane can also be used as a reducing reagent in place of HCOONH_4. A wide variety of functional groups are compatible for both reactions. The key step for both catal … More ytic reactions is the directing group-promoted cleavage of an acyl carbon-oxygen bond in esters, leading to the generation of acyl transition metal alkoxo complexes.(3)The direct carbonylation of C-H bonds in the benzene ring of N-phenylpyrazoles via catalysis by ruthenium or rhodium complexes was achieved. The reaction of N-phenylpyrazoles with carbon monoxide and ethylene in the presence of Ru_3(CO)_<12> or Rh_4(CO)_<12> resulted in the siteselective carbonylation of the ortho C-H bonds in the benzene ring to give the corresponding ethylketones. A variety of functional groups on the benzene ring can be tolerated. N-Phenylpyrazoles have higher reactivities than would be expected, based on the pKa values of the conjugate acid of pyrazole. The choice of solvent for this reaction is significant, and N, N-dimethylacetamide (DMA) gives the best result.(4)The reaction of alkenes with pyridinemethanol and CO in the presence of Rh_4(CO)_<12> resulted in hydroesterification under relatively mild reaction conditions. The use of benzyl alcohol in place of pyridinemethanol gave no reaction. Less