Mukaiyama

Mukaiyama s Reagent (2-Chloro-l-methyl pyridinium Iodide or 2-Fluoro-l-methyl pyridinium p-toulenesulfonate)... 

The use of indium in acpieous solution has been reported by Li and co-workers as a new tool in org nometallic chemistry. Recently Loh reported catalysis of the Mukaiyama-aldol reaction by indium trichloride in aqueous solution". Fie attributed the beneficial effect of water to a eg tion phenomena in connection with the high internal pressure of this solvenf This woric has been severely criticised by... 

Stereoselectivities of 99% are also obtained by Mukaiyama type aldol reactions (cf. p. 58) of the titanium enolate of Masamune s chired a-silyloxy ketone with aldehydes. An excess of titanium reagent (s 2 mol) must be used to prevent interference by the lithium salt formed, when the titanium enolate is generated via the lithium enolate (C. Siegel, 1989). The mechanism and the stereochemistry are the same as with the boron enolate. 

T. Mukaiyama, Organic Keactions Vol. 28, John Wiley Sons, Inc., New York, 1982. 

J. Jaques, A. CoUet, and S. WiUen, Enantiomers, Racemate, and Resolutions,]o m Wiley Sons, Inc., New York, 1981 The Chemical Society of Japan, eds., Kikan Kagaku Sosetsu (No. 6, Resolution of Optical Isomers), Gakkai Shuppan Senta, Tokyo, Japan, 1989 G. C. Barrett ia Ref. 1, Chapt. 10, pp. 338—353 S. Otsuka and T. Mukaiyama, Progress of ylsymmetric Synthesis and Optical Resolution (ia Japanese), Kagaku Dojia, Kyoto, Japan, 1982. 

MUKAIYAMA Slereoselecitveaktol Stereoselective aktol condensation via tin (il) enolates (e g 2)... 

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