McMurry-Fleming olefin synthesis

McMurry-Fleming olefin synthesis. Two laboratories ° have reported the synthesis of the crowded alkene tetraisopropylethylene by reductive coupling of 2,4-dimethyl-3-pentanone yields are 6% and 12%. The NMR indicates that the isopropyl groups of this alkene are not equivalent. 

McMurry, J. E., and M. P. Fleming. 1974. A new method for the reductive coupling of carbonyls to olefins Synthesis of /3-carotene. J. American Chemical Society 96 4708-9. 

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