Origin of the carbonyl addition in the presence of water with various experimentally relevant and "designed" organoindium compounds (chapter 1), allyl-and alkyl-metal compounds (chapter 2) is discovered. The kinetic propensity for 6-mr addition is found to be correlated with lateness of transition states, while the correlation for 4-mr alkylation is sharply distinct from 6-mr allylation, in which the prevailing reasoning cannot resolve this anomalous phenomena....[ Read more ]

Origin of the carbonyl addition in the presence of water with various experimentally relevant and "designed" organoindium compounds (chapter 1), allyl-and alkyl-metal compounds (chapter 2) is discovered. The kinetic propensity for 6-mr addition is found to be correlated with lateness of transition states, while the correlation for 4-mr alkylation is sharply distinct from 6-mr allylation, in which the prevailing reasoning cannot resolve this anomalous phenomena.

In chapter 3, the mechanism of the hydroacylation with 4-alkynal is evolved and involved in complicated and many rapidly rearranged steps. 11-TSa should be responsible to give cyclopentanone in the weak coordinating solvents and for 3-hydroxyl-4-alkynals, rather than the proposed 5-TSa. 11-TSa can show origin of enantio-selectivity. Important roles of explicit coordinating solvents and the side-reaction decarbonylation processes on the rhodium metallacycle intermediates inevitably more favorable than 5-TSa, 6-TSa, 8-TSa and 11-TSa are shown. The origin of trans-addition of Rh-H should proceed from syn-addition, followed by isomerization of C=C bond. The difficulty of the intermolecular hydroacylation is a higher activation barrier of the C-H activation and facile side-reactions.

In Chapter 4, the calculation shows one-step of oxidative addition concerted with hydride or silyl insertion for the intermolecular hydrosilylation reaction, while two-step mechanism for the intramolecular reaction. Hydride insertion in the presence of a NCH ligand is the most favored pathway and rationalizes intermolecular Markovnikov regio-selectivities and endo intramolecular reactions. The key of the trans addition stereochemistry results from the formation of a η²-vinylruthenium or metallacyclopropene intermediate upon hydride-insertion followed by a stereospecific counter-clockwise rotation of the C_α-C_β bond and a facile α-silyl migration through a metallacyclopropene-like transition structure to give a trans addition product.