Cyanotrimethylsilane

Separate experiments showed that chlorotrimethylsilane and cyanotrimethylsilane have a beneficial effect on the reaction rate and diastereoselectivity19. 

The cyanohydrin-forming addition of cyanide or cyanide equivalents (e.g.. cyanotrimethylsilane) to optically active a-amino aldehydes occurs diastereoselectively. 

THF THP TIPS TIPSOTf TMEDA TMS TMSC1 TMSCN TMS I TMSOTf Ts tetrahydrofuran tetrahydropyranyl tri-isopropylsilyl tri-isopropylsilyl trifluoromethanesulphonate AVV,N N -tetramethylethylenediamine trimethylsilyl trimethylsilyl chloride (chlorotrimethylsilane) trimethylsilyl cyanide (cyanotrimethylsilane) trimethylsilyl iodide (iodotrimethylsilane) trimethylsilyl trifluoromethanesulphonate tosyl (p-tolucnesulphonyl)... 

The addition of HCN to aldehydes or ketones produces cyanohydrins. This is an equilibrium reaction. For aldehydes and aliphatic ketones the equilibrium lies to the right therefore the reaction is quite feasible, except with sterically hindered ketones such as diisopropyl ketone. However, ketones ArCOR give poor yields, and the reaction cannot be carried out with ArCOAr since the equilibrium lies too far to the left. With aromatic aldehydes the benzoin condensation (16-54) competes. With oc,p-unsaturated aldehydes and ketones, 1,4 addition competes (15-33). Ketones of low reactivity, such as ArCOR, can be converted to cyanohydrins by treatment with diethylaluminum cyanide (Et2AlCN see OS VI, 307) or, indirectly, with cyanotrimethylsilane (MesSiCN) in the presence of a Lewis acid or base, followed by hydrolysis of the resulting O-trimethylsilyl cyanohydrin (52). The use of chiral additives in this latter reaction leads to cyanohydrins with good asymmetric... 

Cyanotrimethylsilane [7677-24-9] Me3SiCN See related alkylhalosilanes See other cyano compounds C4H9NSi... 

Substitution of fi-nitro sulfides.2 (3-Nitro sulfides in the presence of a Lewis acid undergo displacement reactions with either allyl- or cyanotrimethylsilane. The reaction is considered to involve an episulfonium intermediate, which is then substituted at the more positive carbon (equation I). The reaction proceeds with retention of configuration, and anti (J-nitro sulfides react much more rapidly than... 

As with other non-metal derivatives, reactivity depends on chain-length, branching and degree of halogen substitution. Individually indexed compounds are f Chloromethylphenylsilane, 2810 f Chlorotrimethylsilane, 1304 f Cyanotrimethylsilane, 1665 f Dichlorodiethylsilane, 1683 f Dichlorodimethylsilane, 0902 f Dichloroethylsilane, 0903 f Dichloromethylsilane, 0470 f Dichloromethylvinylsilane, 1208 f Iodotrimethylsilane, 1306 f Methyltrichlorosilane, 0439 f Trichloroethylsilane, 0854 f Trichlorovinylsilane, 0746... 

The chiral titanium reagent preparerd in situ from the chiral 1,4-diol and dichlorodiisopropoxytitanium is expected to be applicable to various reactions catalyzed by Lewis acids. We, therefore, investigated the asymmetric synthesis of cyanohydrins from aldehydes and cyanotrimethylsilane employing the chiral titanium reagent.(20)... 

Firstly, we examined the asymmetric hydrocyanation of 3-phenylpropanal. When 3-phenylpropanal was treated with cyanotrimethylsilane using the chiral titanium alkoxide prepared from dichlorodiisopropoxytitanium and the chiral 1,4-diol 17b in toluene at room temperature, only a trace amount of the... 

Table 8. Asymmetric Hydrocyanation of Aldehydes with Cyanotrimethylsilane...

The optical purity of these cyanohydrins was influenced largely by the reaction temperature and was very low at room temperature. Furthermore, when benzaldehyde was treated with cyanotrimethylsilane in the presence of the chiral titanium reagent and MS 4A at room temperature, followed by stirring the reaction mixture at -65 °C for 1 day, the optical purity of mandelonitrile 23b was ca. 10%. These results indicated that the cyanohydrins were produced as kinetic products in this catalytic process. 

Amino-2-methylpropane, Methylene chloride, 1,3,5-Trifluoro-2,4,6-trinitrobenzene, Potassium hydrogen carbonate, Trifluoroacetic acid, Cyanotrimethylsilane, Nitromethane, Acetonitrile, Sulfuric acid... 

The following procedure is an operatively simple route for the synthesis of bromotrimethylsilane on a preparative laboratory scale from reagents that are readily accessible and inexpensive. This could be a method of choice in some laboratories despite the fact that bromotrimethylsilane is now commercially available (Petrach Systems, Aldrich, or Alpha). Moreover, the procedure also serves as a suitable method for the synthesis of azidotrimethylsilane and isocyanatotrimethylsilane, and is specially useful for the preparation of cyanotrimethylsilane. Thus a mixture of triphenylphosphine dibromide, hexamethyldisiloxane, and a catalytic amount of powdered metal zinc in 1,2-dichlorobenzene is heated under reflux to produce bromotrimethylsilane in nearly quantitative yield, which is simultaneously distilled over a suspension of the corresponding pseudohalogenoacid salt in N, /V-dimethylformamide as solvent.6... 

Review Synthetic applications of cyanotrimethylsilane, iodotrimethylsilane, azidotrimethylsilane, and mcthylthiotrimcthylsilanc have been reviewed (108 references). 

Conjugate addition. In the presence of 1 equivalent of triethylaluminum, cyanotrimethylsilane undergoes conjugate addition to a,/ -enones in high yield. The products arc converted into /J-cyano ketones by acid hydrolysis. The addition is kinetically controlled in toluene at room temperature, but thermodynamically controlled in refluxing THF (equation I). 

A2-Butenolides. A simple route to A2-butenolides from a,/5-enals involves conversion to the O-trimethylsilylcyanohydrin (cyanotrimethylsilane, 4, 542 -543 5, 720 722 6, 632 633), which is then oxidized by PDC (3 equivalents) in DMF. The sequence from geraniol is typical (equation I). 

J. D. Elliott, V. M. F. Choi, and W. S. Johnson, Asymmetric synthesis via acetal templates. 5. Reactions with cyanotrimethylsilane. Enantioselective preparation of cyanohydrins and derivatives, J. Org. Chem. 78 2294 (1983). 

Cleavage of oxetanes.2 In the presence of Znl2, oxetanes are opened by cyanotrimethylsilane regioselectively to y-hydroxy isocyanides, which undergo acid-catalyzed hydrolysis to y-amino alcohols. 

Addition of CN Cyanotrimethylsilane, 87 Sodium cyanide, 185 Addition a to carbonyl groups Chloromethyldiphenylsilane, 74... 

Magnesium-Methanol, 170 Miscellaneous reductions Cyanotrimethylsilane, 87 Nickel boride, 197 B -3-Pinany 1-9-borabicy clo[3. 3.1 ]no-nane, 249... 

Amino alcohols Cyanotrimethylsilane, 87 Lithium aluminum hydride-Sodium... 

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