Iodide, samarium

Samarium iodide (Sml2) gives the same reaction. Benzoyl chloride was coupled to give benzil by subjecting it to ultrasound in the presence of Li wire 2 PhCOCl -I-... 

Indium metal reduces the pyridine ring in quinoline in aqueou sethanol solution.Samarium iodide (Sml2) reduces pyridine in aqueous THF ° and phenol in MeOH/KOH. ... 

Samarium iodide promotes this addition reaction. In a related reaction, simple alkene units add to esters in the presence of sodium and liquid ammonia to give an alcohol. " °... 

It has been shown recently that the selective reductive homo-coupling polymerization of aromatic diisocyanates via one electron transfer promoted by samarium iodide in the presence of hexamethylphosphoramide [PO(NMe2)3] (HMPA) can produce poly(oxamide)s in nearly quantitative yield (Scheme 9). 

Another well-known transformation of carbonyl derivatives is their conversion to pinacols (1,2-diols) via an initial one-electron reduction with highly active metals (such as sodium, magnesium, aluminum, samarium iodide, cerium(III)/ I2, yttrium, low-valent titanium reagents (McMurry coupling), etc.), amines, and electron-rich olefins and aromatics as one-electron donors (D).43 Ketyl formation is rapidly followed by dimerization44 (equation 22). 

Zard and coworkers have developed a synthesis of substituted dienes by reductive elimination of allylic nitroacetates (equation 33)66. Allylic nitroacetates can be prepared by condensation of nitromethane with the carbonyl compound followed by addition of formaldehyde and acetylation67. Reductive elimination can be carried out by employing either chromous acetate or samarium iodide. 

A radical anion is involved in the samarium iodide-induced cyclization of the pyrrole derivative 58 (Scheme 19) <20030L4305>. 

Carree, F. Gil, R. Collin, J. (2004) Samarium iodides catalyzed meso-epoxides ring opening by aromatic amines.. Tetrahedron Lett., 45 7749-7751. 

When 1,2-dihydroquinazolines are actually desired as the reaction product, they can often be contaminated with their conjugated analogs due to spontaneous dehydrogenation <2000JME4479>, but this can be avoided under reductive conditions, as demonstrated by the preparation of 2-substituted-l,2-dihydroquinazolines 815 by the reductive condensation of 2-nitrobenzamides 814 with aldehydes in the presence of samarium iodide <2002JHC1271>. 

Samarium iodide-induced radical reaction of di(2-nitrophenyl)disulfides with ot-bromoketones has also been reported (Scheme 65) <2001HAC156, 2001TL3125>. 

A samarium iodide-water-amine mixture has been shown to be effective for cyclizations of 0-cyclohexenyliodo-phenols and pyridines into heterocycles <2003OBC2423>. 

Oxindoles are prepared using a solid-phase Pummerer reaction. Thus, the immobilized amide 182 undergoes the Pummerer rearrangement on treatment with TFAA and boron trifluoride diethyl etherate (BF3 Et20) (Equation 118). Cleavage of the oxindole from the linker is achieved using samarium iodide and 1,3-dimethyl-3,4,5,6-tetrahydro-2(lH)-pyrimidinone (DMPU) <2003CC2380>. 

O Neill and Helquist have also discovered that 1,10-phenanthroline 48 undergoes samarium iodide-promoted coupling with ketones and this process has been applied to the chiral ketone (—)-thujone 53 to give the corresponding phenanthroline 54 as a single stereoisomer (Equation 5) <19990L1659>. 

There are extensive possibilities for the formation of geometric and optical isomers in eight-coordinate complexes. Thus far. apparently only one pair has been completely characterized The diglyme [= di(2-methoxyethyl)etherl adduct of samarium iodide. Sml rO(CH2CH2OCH3)2]2. has been isolated in both cis and irons forms. The trans complex (Fig. 12.39a) has a center of symmetry Thus, the I—Sm—1 angle is exactly 180. and the molecule is a bicapped trigonal antiprism. The cis isomer (Fig. (2.39b) has ihe lower symmetry of a distorted dodecahedron with I—Sm—I angles of 92 > ... 

D. Mazdas, T. Skrydstrup, O. Doumeix, and J.-M. Beau, Samarium iodide induced intramolecular C-glycoside formation Efficient radical formation in the absence of an additive, Angew. Chem. hit. Ed. Engl. 33 1383 (1994). 

A related method involving the samarium iodide-mediated coupling of a-benzoyloxy lactones with ketones has been reported recently by Enholm [164,165]. 

Thus, this method takes advantage of a relatively rapid 9-endo-trig cyclization, rather than undergoing other possible reactions with samarium iodide [32],... 

The reductive elimination of 0-hydroxyimidazoyl sulfones by samarium iodide was claimed to be an improved variation of the Julia olefin synthesis [421]. 

Samarium Compounds t-Butoxydiiodosamarium, 272 Diiodomethane-Samarium, 113 Diiodomethane-Samarium iodide, 113 Samarium, 113... 

Allyl acetates can also be reduced by Pd° catalysts in conjunction with samarium iodide,303 model NAD(P)H compounds306 and under electrochemical conditions (equations 107 and 108).307... 

Both samarium iodide and ytterbium triisopropoxide catalyse the ring opening45 of epoxides by TMS-azide in the latter case, due to an acidic work-up, the products are isolated as vicinal azido alcohols. 

Appropriate functionalization of C=N bonds can greatly assist their asymmetic reduction. In particular, the reduction of N-acyl hydrazones with a rhodium complex of the ligand DuPHOS (P13) represents an outstanding example. In this process (Scheme 62) a product of up to 97% e.e. is obtained in high yield. After the reduction, samarium-iodide cleavage of the N—N bond gives the product amine273,274. 

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