Ketone To Vinyl Iodide

Such chiral moieties are widespread in natural products and the development of.

Ketone to vinyl iodide. Various ketones as the electrophiles react in a one pot three component coupling with an aluminum allenoate intermediate derived from ethyl propiolate and alluminium iodide to yield β iodo morita baylis hillman adducts with high yield and excellent z stereoselectivity. We considered using in situ generated vinyl boron ate complexes vi derived from enantioenriched boronic esters v and vinyllithium in a radical polar crossover reaction with various alkyl iodides and report herein that this key transformation followed by oxidation offers a new route to α chiral ketones. Vinyl iodides are versatile molecules that serve as important building blocks and precursors in organic synthesis. The ketone necessary for the hydrazone to vinyl iodide transformation was then the enone 2.

This optically active enone 2 was prepared in 7 steps from optically active wieland miescher ketone 1 5 6 the hydrazone 3 was prepared by treatment of racemic 2 with hydrazine hydrochloride in ethanol in 9896 yield. Ryu synlett 2007 59 62. Hydrazone iodination is an organic reaction in which a hydrazone is converted into a vinyl iodide by reaction of iodine and a non nucleophilic base such as dbu first published by derek barton in 1962 the reaction is sometimes referred to as the barton reaction although there are many different barton reactions or more descriptively as the barton vinyl iodine procedure. This reaction is relatively slow compared to the formation of the above equilibrium.

Rate constants for the reaction over the temperature range 281 355 c fit the arrhenius equation. Application of pho 3 p halogen based reagents allows the preparation of vinyl halides in good to excellent yields from enolizable ketones whereas aldehydes afforded the. The use of catalytic amounts of copper iodide and trans n n dimethylcyclohexane 1 2 diamine in the presence of tetramethylammonium chloride or. 15 2433 2436 1993 0040 4039 93 6 00 00 printed in great britain perganton press ltd the reaction of vinyl phosphates with iodotrimethylsilane.

A new method for preparation of vinyl iodides from ketones is described. Synthesis of vinyl iodides from ketones koo lee and david f wier department of chemistry university of iowa iowa city iowa 52242 abstract. The unimolecular decomposition of 2 iodo 3 butanone to methyl vinyl ketone and hydrogen iodide was also measured in the same system. 18531 94 7 offered by s.

In organic chemistry a vinyl iodide also known as an iodoalkene functional group is an alkene with one or more iodide substituents.