1422157-33-2

Downstream Products

• 1422157-34-3 tert-butyl (+)-(1R,2R,S_S)-1-dimethylphosphono-2-(p-tolylsulfinyl)-2-methylcyclopropane-1-carboxylate 
• 1422157-35-4 tert-butyl (+)-(1R,2R)-1-dimethylphosphono-2-(p-tolylsulfonyl)-2-methylcyclopropane-1-carboxylate 

Relevant academic research and scientific papers

Stereoselective Cyclopropanation as a Way to 1-Aminocyclopropane-1-phosphonic Acids: Rationale for Phosphoryl Group Migration

Asymmetric cyclopropanation of vinylphosphonates by using (S)-dimethylsulfonium(p-tolylsulfinyl)methylide and subsequent highly stereoselective methylation provided substituted cyclopropylphosphonates, which are useful intermediates in the synthesis of rigid aminophosphonic acids. However, in some examples desulfinylation by iPrMgCl led to 1,2-migration of the phosphoryl group. The scope of this transformation was investigated by changing the temperature, electronegativity of the substituent α to phosphoryl group, and the configuration of the cyclopropylphosphonates. It was found that a cis relationship between the phosphoryl and sulfinyl groups led exclusively to the product of migration. It was proposed that the rearrangement occurred as an internal process in a concerted manner. The feasibility of an intramolecular mechanism was supported by DFT calculations. The products of desulfinylation with retained structure were used for the synthesis of enantiomerically pure 1-aminocyclopropane-1-phosphonic acids. Desulfinylation of cyclopropylphosphonates by reaction with iPrMgCl results in 1,2-migration of the phosphoryl group. A relationship between the structure and course of the sulfinyl-metal exchange suggests that mechanistically this transformation is an internal process. An isomerization mechanism is verified by DFT calculations.

Stereoselective cyclopropyl phosphonate formation using (S)-dimethylsulfonium-(p-tolylsulfinyl)methylide. Unusual phosphoryl group migration

Methylation of t-butyl-1-dimethylphosphono-2-p-tolylsulfinyl cyclopropanecarboxylic ester occurs with full inversion of the configuration, but the stereochemistry of carbanion formation is structure-dependent. Reaction of cyclopropyl sulfoxide with i-PrMg