Synthesis of Bifunctional Allylic Compounds by Using Cyclopropenes as Functionalized Allyl Equivalents

The synthesis of uncommon bifunctional allylic derivatives bearing a silane and an alcohol within the same allylic framework is reported. This method relies on the coupling of hydrosilanes with substituted and functionalized cyclopropenes, which deliver the allyl fragment. Rhodium(II) catalysts provide regioselective access to vinyl carbene intermediates, which easily undergo Si?H bond insertions. The transformation occurs with complete atom economy and shows a remarkably broad scope, including a intramolecular version for the synthesis of cyclic O?Si‐linked compounds as well as the synthesis of the corresponding allyl amines.     

Carbenes,related intermediates,and small-sized cycles: contribution from Professor Nefedov’s laboratory

The review summarizes some of the most prominent results obtained in the laboratory headed by Academician Oleg M. Nefedov at the N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences in the field of chemistry of carbenes, their heavy analogs, and related intermediates, as well as small-sized cycles. Those include elaboration of safe methodology of cyclopropanation using diazomethane, development and extension of synthetic applications of diazoesters and other diazo compounds in the preparation of valuable chemical products, design of functionalized alkynylcyclopropanes on the basis of alkynylcarbene reactions, creation of versatile synthetic approaches to preparation of various practically useful fluoroorganic compounds on the basis of reactions of fluorocarbenes, development of synthetic applications of heavy carbene analogs and synthesis of small-sized heterocycles containing silicon and germanium atoms, analysis of mechanisms of some important reactions of carbenes, their analogs and related intermediates on the basis of physicochemical studies, direct spectroscopic studies of various labile intermediates of chemical reactions.     

Asymmetric Copper-Catalyzed Carbomagnesiation of Cyclopropenes

The highly diastereo- and enantioselective formation of polysubstituted cyclopropanes was easily achieved through the asymmetric copper-catalyzed carbomagnesiation reaction of nonfunctionalized cyclopropene derivatives. The carbometalated species generated in situ readily undergo C−C and C−X bond-forming reactions with various electrophiles with complete retention of configuration.     

Synthesis of 1,2-diferrocenyl-3-(diacylmethylidene)cyclopropenes and 1,1-diacyl-2,3-diferrocenyl-4-methylsulfanylbuta-1,3-dienes, their structures and electrochemical properties

2,3-Diferrocenyl-1-morpholinocyclopropenylium tetrafluoroborate reacts with 1,3-diketones in the presence of triethylamine to give 3-diacylmethylidene-1,2-diferrocenylcyclopropenes (8a-d). Under similar conditions, 2,3-diferrocenyl-1-methylsulfanylcyclopropenylium iodide affords 8a-c (∼25-30%) and 1,1-diacyl-2,3-diferrocenyl-4-methylsulfanylbuta-1,3-dienes (10a-c) (∼50-60%). The structures of the products obtained were established based on the data from ¹H (1D NOE) and ¹³C NMR spectra and X-ray diffraction analysis. Electrochemical properties of several (diacylmethylidene)diferrocenylcyclopropenes (8a-c) and 1,1-diacyl-2,3-diferrocenyl-4-methylsulfanylbuta-1,3-dienes (10a-c) are studied.