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- Simmons–Smith reaction - Wikipedia
The Simmons–Smith reaction is an organic cheletropic reaction involving an organozinc carbenoid that reacts with an alkene (or alkyne) to form a cyclopropane [1] [2] [3] It is named after Howard Ensign Simmons, Jr and Ronald D Smith
- Simmons-Smith Reaction - Organic Chemistry Portal
Various research groups have developed variants of the Simmons-Smith cyclopropanating reagent through the replacement of the iodide ligand on the zinc atom with a strongly electron-withdrawing substituent
- Simmons-Smith Reaction: Definition, Mechanism, and Examples
Simmons-Smith reaction is an asymmetric reaction in which a carbenoid adds to an alkene or alkyne to form a cyclopropane It is an essential reaction involving an organozinc reagent The reaction is typically conducted using diiodomethane in combination with metallic zinc and copper (Zn(Cu))
- 8. 9: Addition of Carbenes to Alkenes - Cyclopropane Synthesis
One common example is the stereospecific Simmon-Smith reaction which utilizes the carbenoid - ICH 2 ZnI The (iodomethyl) zinc iodide is formed in situ via the mixing of Zn-Cu with CH 2 I 2 If this ICH 2 ZnI is in the presence of an alkene, a CH 2 group is transferred to the double bond to create cyclopropane
- Cyclopropanation of Alkenes and the Simmons-Smith Reaction
In this tutorial, we’re exploring two fascinating reactions: Cyclopropanation and the Simmons-Smith Reaction Though distinct, both reactions share a common objective—they transform alkenes into corresponding cyclopropanes
- Simmons smith reaction: Mechanism, important uses
Iodomethyl zinc iodine is known as a Simmons-smith reagent, which can be prepared by the reaction of diidomethane and a copper-zinc couple When olefins react with Simmons smith reagent, the carbene is added to the carbon-carbon double bond to form cyclopropane
- Simmons-Smith Cyclopropanation - an overview - ScienceDirect
The Simmons–Smith reaction is a powerful method for preparing cyclopropanes from olefins using zinc carbenoids (IZnCH 2 I, EtZnCH 2 I, Zn(CH 2 X) 2) 7a,278,278a A variety of versions of this reaction have been developed and new carbenoids species have been made
- Reaction Pathways of the Simmons−Smith Reaction
The cyclopropanation of ethylene with a lithium carbenoid or a zinc carbenoid [Simmons−Smith (SS) reagent] goes through two competing pathways, methylene transfer and carbometalation Both processes are fast for the lithium carbenoid, while, for the zinc carbenoid, only the former is fast enough to be experimentally feasible
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