15232-90-3Relevant articles and documents
Copper-catalyzed alkene arylation with diaryliodonium salts
Phipps, Robert J.,McMurray, Lindsay,Ritter, Stefanie,Duong, Hung A.,Gaunt, Matthew J.
supporting information; experimental part, p. 10773 - 10776 (2012/08/07)
Alkenes and arenes represent two classes of feedstock compounds whose union has fundamental importance to synthetic organic chemistry. We report a new approach to alkene arylation using diaryliodonium salts and Cu catalysis. Using a range of simple alkenes, we have shown that the product outcomes differ significantly from those commonly obtained by the Heck reaction. We have used these insights to develop a number of new tandem and cascade reactions that transform readily available alkenes into complex arylated products that may have broad applications in chemical synthesis.
Regio- and enantioselective substitution of primary endocyclic allylic sulfoximines with organocopper and organocuprate reagents. The importance of iodide for the allylic substitution with organocopper compounds
Gais, Hans-Joachim,Müller, Harald,Bund, J?rg,Scommoda, Matthias,Brandt, Jochen,Raabe, Gerhard
, p. 2453 - 2466 (2007/10/02)
The endocyclic N-substituted allylic sulfoximines 17-20 and 26 were synthesized from the corresponding cycloalkanones and the various (S)-5-(lithiomethyl)-S-phenylsulfoximines in enantiomerically pure form in yields of 60-70% in a process involving the isomerization of the intermediate vinylic sulfoximines. Desilylation of 26 gave the parent N-H sulfoximine 27 from which the N-sulfonylsulfoximines 28 and 29 were prepared. The X-ray crystal structure of 28 was determined. The allylic sulfoximines 17-20 and 26-29 did not racemize or rearrange thermally to the corresponding allylic sulfinamides. Reaction of the allylic sulfoximines 18, 28, and 29 with the organocuprate reagents 2/LiI, 35/LiI, and 47/LiI led with α-selectivities of 92:8 to 99:1 to the endocyclic alkenes 39 in good to high yields. Reaction of 17-20, 28, and 29 with the organocopper reagents 5/LiI, 30/LiI, 31/LiI, 32/LiI, 33/LiI, 34/LiI, and 37/LiI in the presence of BF3 resulted in the formation of the exocyclic alkenes 38, 41, 43, and 45, respectively, in good to high yields with γ-selectivities of 80:20 to 99:1. The sulfonimidoyl group imparts asymmetric induction to the substitution in the range of 27-90% ee. The (S)-sulfonimidoyl group leads to a preferential bond formation from the si side of the double bond. From the sulfoximines 18 and 26-29 the N-methylsulfoximine 18 and the N-tosylsulfoximine 28 showed the highest and lowest reactivity with the butylcopper reagent 32/LiI in the presence of BF3, respectively, while in the absence of BF3 only 29 reacted. The Lewis acid most likely serves to activate the N-methyl- and N-tosylsulfoximines or intermediates thereof through coordination at the sulfonimidoyl and sulfonyl group. Reaction of the sulfoximines 18 and 29 with pure Me3SiCH2Cu (34) revealed a strong rate acceleration by LiI and an even stronger one by Bu4NI. This points to the existence of a heteroleptic cuprate or a related compound as reactive species. In substitutions with the Yamamoto reagents RCu/MX/BF3, the halide is important and a reaction between RCu and BF3 does not have, at least in the case of allylic sulfoximines, to be invoked. In reactions of 17-20 besides the alkenes, the sulfinamide ent-4 was formed with an ee value of 97% in high yield with retention of configuration. The absolute configuration of the exocyclic alkenes 38, 41, and 45 was determined by ozonolysis to the corresponding cycloalkanones followed by their conversion to the corresponding lactones and/or CD measurement of the former.
Fluoride ion mediated intramolecular sulfenylation of α-silyl sulfones: Ramberg-Ba?cklund annulation to exocyclic fused olefins
Scarpetti, David,Fuchs, Philip L.
, p. 8084 - 8090 (2007/10/02)
A series of α-trimethylsilyl-substituted phenyl sulfones bearing an ω-p-toluenethiosulfonyl α-substituent were synthesized and subjected to treatment with tetra-n-butylammonium fluoride to provide the corresponding monocyclic sulfides (6-, 7-, and 8-membe
Palladium-Catalyzed Regio- and Stereoselective Reduction of Allylic Compounds with LiHBEt3. Application to the Synthesis of Co-enzyme Q10
Mohri, Mitsunobu,Kinoshita, Hideki,Inomata, Katsuhiko,Kotake, Hiroshi,Takagaki, Hidetsugu,Yamazaki, Keiji
, p. 1177 - 1180 (2007/10/02)
Regio- and stereoselective desulfonylation of allylic sulfones with LiHBEt3 in the presence of a catalytic amount of was succesfully applied to the synthesis of co-enzyme Q10.It was found that this reduction system was applicable to a wide variety of allylic functional groups.
