Addition of organometallic compounds

Additions of organometallic compounds to 2-azelidinones such as 1 or 4 bearing a leaving group in the 4-position preferentially or exclusively afford tram-3,4-substituted /(-lactams 3 or 6. Therefore, the participation of an A -acylinline intermediate such as 2 or 5 which is attacked from the less hindered side is probable14-16. This has been exploited for the synthesis of carbapenem antibiotics, e.g., thienamycin (7)16. 

Addition of Organometallic Compounds to a,/MJnsaturated Carbonyl Compounds... 

As with the reduction of aldehydes and ketones (16-23), the addition of organometallic compounds to these substrates can be carried out enantioselectively and diastereoselectively. Chiral secondary alcohols have been obtained with high ee values by addition to aromatic aldehydes of Grignard and organolithium compounds in the presence of optically active amino alcohols as ligands. ... 

For a review of additions of organometallic compounds to C=S bonds, both to the sulfur (thiophilic addition) and to the carbon (carbophilic addition), see Warded, J.L. Paterson, E.S. in Hartley Patai The Chemistry of the Metal-Carbon Bond, vol. 2 Wiley NY, 1985, p. 219. See pp. 261-267. 

For reviews of the addition of organometallic compounds to carbonyl groups, see Eicher, T. in Patai, Ref. 2, p. 621 Kharasch, M.S. Reinmuth, O. Grignard Reactions of Nonmetallic Substances, Prentice-Hall Englewood Cliffs, NJ, 1954, p. 138. For a review of reagents that extend carbon chains by three carbons, with some functionality at the new terminus, see Stowell, J.C. Chem. Rev., 1984, 84, 409. 

Addition of vinylic organometallic compounds to unsaturated carbonyl compounds addition of organometallic compounds to acetylenic carbonyl compounds... 

Addition of organometalic compounds to nitrones is known as an efficient method of enantioselective synthesis of primary amines that can be easily obtained by the reduction of hydroxylamines which are the products of nucleophilic addition. 

Diastereoselective addition of a wide range of Grignard reagents to C -alkyl and C-aryl-A-[a.-phenyl- or u-methyl-j3-(benzyloxy)ethyl nitrones is determined by the presence of a stereogenic A -substituent (136, 137). High diastereoselectiv-ity in the addition of organometalic compounds to A-(( i-methoxyalkyl) nitrones can be explained by a simple chelation model (Scheme 2.132) (136). 

Reactions at the Carbonyl Group 1,2-Additions of Organometallic Compounds ... 

Various chiral diaminoalcohols (91, 92, 93, 94) were synthesized starting from commercially acailable (S)-proline. The enantioselective addition of organometallic compounds to aldehydes in the presence of the aminoalcohols was investigated. 

Addition of Organometallic Compounds to Activated Double Bonds Hydro-alkyl-addition... 

As with the Michael reaction (5-17) the 1,4 addition of organometallic compounds has been performed diastereoselectively517 and enantioselectively.518 In one example of the latter,519 a, (3-unsaturated sulfoxides that are optically active because of chirality at sulfur (p. 100) have given high enantiomeric excesses, e.g.,520... 

Hydroboration-oxidation of alkenes 5-18 Addition of organometallic compounds to unsaturated alcohols 5-20 Addition of CH, and H to allylic alcohols... 

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