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New Hal-de-H reaction in Organic Chemistry


Key words: terminal olefin, iodoallyl derivatives, allyl derivatives, selective monohalogenation


A new Iodo-de-H reaction (3/Iodanylium-de-hydrogenation) was developed for the process of selective non-radical monoiodination of olefins. This reaction allows for the manufacture of different monoiodo allyl derivatives in one step at room temperature during several minutes in accordance with the reaction Scheme 1. We are not using expensive catalysts or expensive reagents for this transformation.


Scheme 1
Scheme 1: General scheme of non radical 3/iodanylium-de-hydronation of terminal olefins.

This newly invented transformation was named in accordance with IUPAC recommendations (Nomenclature For Organic Chemical Transformations). It is worthwhile to mention that this transformation belongs to synchronous allylic substitution class of chemical transformations with SEi' or cyclo-3/1/AEDnAnDH mechanism (System For Symbolic Rrepresentation Of Reaction Mechanisms). This process manifests a high level of selectivity and conversion (> 95%) during several minutes of the reaction at room temperature. Such parameters characterize the efficiency and economic value of this process compared to radical halogenation, broadly used in organic chemistry and industry. The general character and possible broad application of this Hal-de-H transformation in organic chemistry was experimentally demonstrated using organic structures with different R groups in formula 1 (Scheme 2).


Scheme 2
Scheme 2: 3/Iodanylium-de-hydronation of terminal olefines. Reaction sites in substrates are makred in red.

The unique synchronous l-de-H character of this reaction was revealed by studying the reaction mechanism (SEi' mechanism). This reaction is very selective and industrially viable for synthesis of iodo allyl derivatives or other allyl derivatives through halogen allyl intermediates. Both reactions of monohalogenation and nucleophilic substitution can be performed in one apparatus as one-pot synthesis.



Scheme 3
Scheme 3: Experimental examples of synthesis of different allyl derivatives through the use of Hal-de-H transformation and subsequent nucleophilic substitution reaction with XY nucleophilic reagents.

Proposal

We are searching for industrial partners who are interested for these novel and practically feasible transformations. We will provide industrial partners with our expertise on synthesis of any iodallyl derivatives. We may also provide partners with our research work on the optimization of the reaction parameters for these transformations. We may deliver to interested partners samples of described or analogous products.