91523-92-1

Upstream product

• 98-81-7 1-bromovinylbenzene 
• 100-42-5 styrene 
• 102921-26-6 (1,2-dibromoethyl)benzene 
• 524-38-9 N-hydroxyphthalimide 
• 14900-39-1 phenylvinylboronic acid 

Downstream Products

• 2892-42-4 (1R,2S,3S)-cyclopropane-1,2,3-triyltris(phenylmethanone) 

Relevant academic research and scientific papers

Rh(III)-Catalyzed C-H Activation-Initiated Directed Cyclopropanation of Allylic Alcohols

We have developed a Rh(III)-catalyzed diastereoselective [2+1] annulation onto allylic alcohols initiated by alkenyl C-H activation of N-enoxyphthalimides to furnish substituted cyclopropyl-ketones. Notably, the traceless oxyphthalimide handle serves three functions: directing C-H activation, oxidation of Rh(III), and, collectively with the allylic alcohol, in directing cyclopropanation to control diastereoselectivity. Allylic alcohols are shown to be highly reactive olefin coupling partners leading to a directed diastereoselective cyclopropanation reaction, providing products not accessible by other routes.

Rh(III)-Catalyzed C-H Activation-Initiated Directed Cyclopropanation of Allylic Alcohols

We have developed a Rh(III)-catalyzed diastereoselective [2+1] annulation onto allylic alcohols initiated by alkenyl C-H activation of N-enoxyphthalimides to furnish substituted cyclopropyl-ketones. Notably, the traceless oxyphthalimide handle serves three functions: Directing C-H activation, oxidation of Rh(III), and, collectively with the allylic alcohol, in directing cyclopropanation to control diastereoselectivity. Allylic alcohols are shown to be highly reactive olefin coupling partners leading to a directed diastereoselective cyclopropanation reaction, providing products not accessible by other routes.

Rhodium(III)-Catalyzed Cyclopropanation of Unactivated Olefins Initiated by C-H Activation

We have developed a rhodium(III)-catalyzed cyclopropanation of unactivated olefins initiated by an alkenyl C-H activation. A variety of 1,1-disubstituted olefins undergo efficient cyclopropanation with a slight excess of alkene stoichiometry. A series of mechanistic interrogations implicate a metal carbene as an intermediate.

Intermolecular Carboamination of Unactivated Alkenes

Herein, we report the first example of group transfer radical addition of O-vinylhydroxylamine derivatives onto unactivated alkenes. By utilizing O-vinylhydroxylamine derivatives as both the N- and C-donors, this reaction enables intermolecular carboamination of unactivated alkenes in an atom economical fashion. As the process is initiated through N-radical addition followed by C-transfer, linear carboamination products are afforded. This differs from canonical radical carbofunctionalization of olefins, which typically favors branched product owing to initiation by C-radical addition.

Synthesis of α-oxygenated ketones and substituted catechols via the rearrangement of N-enoxy- and N-aryloxyphthalimides

A common approach to the synthesis of α-oxygenated carbonyl compounds and catechols is the treatment of a carbonyl compound or a phenol with an electrophilic oxygen source. As an alternative approach to these important structures, formal [3,3]-rearrangements of N-enoxyphthalimides, N-enoxyisoindolinones, and N-aryloxyphthalimides have been explored. When used in combination with an initial Chan-Lam coupling, these transformations facilitate the dioxygenation of alkenylboronic acids for the synthesis of α-oxygenated ketones and the dioxygenation of arylboronic acids for the synthesis of catechols. The rearrangements of N-enoxyisoindolinones have also been shown to be diastereoselective.

Rh(III)-catalyzed cyclopropanation initiated by C-H activation: Ligand development enables a diastereoselective [2 + 1] annulation of N-enoxyphthalimides and alkenes

N-Enoxyphthalimides undergo a Rh(III)-catalyzed C-H activation initiated cyclopropanation of electron deficient alkenes. The reaction is proposed to proceed via a directed activation of the olefinic C-H bond followed by two migratory insertions, first across the electron-deficient alkene and then by cyclization back onto the enol moiety. A newly designed isopropylcyclopentadienyl ligand drastically improves yield and diastereoselectivity.

Preparation of α-oxygenated ketones by the dioxygenation of alkenyl boronic acids

Two in two: Dioxygenation of alkenyl boronic acids has been achieved with N-hydroxyphthalimide. The two-step process involves etherification of an alkenyl boronic acid with N-hydroxyphthalimide followed by a [3,3] rearrangement. The dioxygenated product can then be hydrolyzed to form either the corresponding α-hydroxy ketone or the α-benzoyloxy ketone. Copyright