Cuprous iodide-Grignard reagents

ALLYLIC ALCOHOLS Benzeneselenol. 9-Borabicyclo[3.3.11 nonane. n-Butyllithium. Cuprous iodide-Grignard reagents. Diethylaluminum 2,2,6,6-tetramethylpiperidide. Fluorodimethoxyborane. rrans-l-Tri-n-butylstannyl-propene-3-tetrahydropyranyl ether. 

Cuprous iodide catalyzes the reaction of various alkyl chlorides, bromides, and iodides in hexamethylphosphoric triamide (HMPT), to give the complexed product RaSnXj, which can then be further alkylated with a Grignard reagent, or can be hydrolyzed to the oxide and converted into various other compounds, R2SnY2 (43). This promises to be a useful laboratory method, e.g.,... 

The above-mentioned study was followed by a report of the groups of Ji, Loh and coworkers, who reported the application of a catalyst based on cuprous iodide and Tol-BINAP for the same purpose . Noteworthy is that the effective use of a C2-symmetric ligand in this reaction marks the end of the aforementioned metal-differentiating coordination concept. It was shown that a variety of Grignard reagents could be used for the... 

Birch and Smith found that cupric acetate is superior to the usuaUy used cuprous bromide as catalyst for the 1,4-addition of Grignard reagents to aj3-unsaturated ketones. Thus 19-nortestosterone (1) in the presence of cupric acetate adds methyl-magnesium iodide to give 2, derived from 1,4-addition, in high yield. 

CO2). A partial solution to this problem is reaction of the vinyl Grignard reagent with alkyl halides in the presence of cuprous iodide [Cu(I)I], which does little for the initial loss of stereochemistry upon formation of... 

Nucleophilic ring-opening of epoxide 53 with Grignard reagent 55 in the presence of cuprous iodide affords 56. A Mitsunobu inversion of the free hydroxy group followed by lactonization and conversion to an or /io-lactone provides 57. 

The spatial bulk of vicinal er butyldimethylsilyloxy protection exerts a significant role in controlling rotational isomeric population. Diethyl (4iS, 5 S)-4,5-bis( 6r -butyldimethylsilyl-oxy)-(2 , 6.E)-octadienedioate (694), prepared from 24 [18] by acidic deprotection followed by reprotection with fer butyldimethylsilyl triflate in the presence of triethylamine [211], exists as the conformer 695 even at room temperature. Nucleophilic attack at the jS-carbon of the enoate moiety of 695 should occur only toward the two Ti-faces, which are exposed to the outside of the molecule. Michael addition of several Grignard reagent-cuprous iodide mixtures (1 1) results in the isolation of a single enantiomer 696a-d in every case. 

KETONES Bis(phenylthio)methane. N,N-Dimethyldithiocaiboamoyl acetonitrile. Grignard reagents. Mangane.se(II) iodide. Phenylsileninyl chloride. Thalliuni(lll) acetate. Vanadiumdl) chloride. d-KETOPHOSPHONATES Cuprous iodide. p-LACTAMS Oxygen. Sodium hydride. 

The synthetic utility of the prenyl Grignard reagent has been extended by its regioselective a-alkylation with alkyl halides induced by cuprous iodide, and by its y-alkylation with alkyl tosylates. The former conditions have been utilized in a straightforward new synthesis of geraniol (Scheme 28). Chromous-salt induced... 

Spry has reported that cis-P-halo-a,P-unsaturated sulfoxides, on treatment with Grignard reagents, react to form carbon-sulfur bonds, and has used this methodology as part of the preparation of 5(l)-C(2)-secocephems [70], while Posner found that a,P-unsaturated aryl sulfoxides were easily reduced to the corresponding sulfides upon treatment with ethylmagnesium bromide/10% cuprous iodide with retention of double bond stereochemistry [71]. 

Cuprous chloride coordinated with A,A,A, A -tetramethylethylenediamine is a good catalyst for the cross-coupling of aryl Grignard reagents and alkyl iodides (Onuma and Hashimoto, 1972). 

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