Organometallics reacting with

Substituted gem-dimetallic compounds, readily obtained via allylation of alkenyl organometallics, react with aldehydes in the presence of BF3-Et20 but do not react with ketones. When alkylidenemalonates are used instead of aldehydes, the Z-olefins see (E) (Z) Isomers) are obtained with a very high stereoselectivity (Scheme 35). A transmetallation reaction with copper cyanide significantly increases the reactivity of gm-dimetallic derivatives via formation of 1,1-zinca cyanocuprates. Indeed, when these compounds react with... 

Organometallics react with COj to give O-bonded rather than C-bonded products . 

Phenylselenomethyl phosphonates and (phenylseleno)chloromethane have been metallated by NaH and Bu OK, respectively (Scheme 28, a and b Scheme 29). The former organometallics react with carbonyl compounds and dirratly produce vinyl selenides (Scheme 28, a and whereas the second decomposes to phenylselenomethylene which adds stereospecifically to alkenes and leads to phenyl-selenocyclopropanes in reasonably good yields (Scheme 29). 

Since organometallics react with acids (Section 8.2.4), they can be used only in basic or neutral media and in aprotic solvents. The most common reaction is Sjs[2 substitution. 

Organometallics react with this sink by addition to the multiple bond (path Ad r). The more covalent, less reactive organometallics, like R2Cd, react very slowly with almost all of these sinks, whereas organomagnesiums, RMgX, and organolithiums react quickly. Complexation of the metal ion to the Y heteroatom catalyzes this reaction. Organometallics react much faster as nucleophiles with polarized multiple bonds than as bases with the adjacent C-H bonds, (carbon-acid, carbon-base proton transfer is slow). C=Y example ... 

Organometallics react with Tl halides to produce C—Tl bonds. The actual Tl... 

Organometallics react with TI halides to produce C—TI bonds. The actual TI... 

Type I crotyl organometallics react with aldehydes, presumably via chair-like transition states, such that the stereochemical information present in the reagent is transmitted to an anti (from ( )-alkene precursors) or a syn (from (Z)-alkene precursors) relationship about the new C—C bond of the product (Scheme 3). A detailed analysis of possible transition states appears in a subsequent section. Type I stereoselectivity has been observed for crotyl organometallics incorporating boron, aluminum, silicon and tin (thermal reactions). 

METHYL-PHENYLENE ISOCYANATE (584-84-9) CjHsNjOj Combustible liquid. Forms explosive mixture with air [explosion limits in air (vol %) 0.9 to 9.5 flashpoint 260°F/127°C autoignition tenq) 1148°F/620°C Fire Rating 1], Contact with strong oxidizers may cause fires and explosions. Inconqiatible with ammonia, amides, glycols, caprolactam solution organometallics. Reacts with water, steam. 

CRESORCINOL DIISOCYANATE (584-84-9) Forms explosive mixture with air (flash point 260°F/127°C). Incompatible with strong acids, caustics, ammonia, amines (may cause foam and spatter), amides, alcohols, glycols, caprolactum solution, organometallics. Reacts with water, acids, or alcohol, causing violent foaming and spattering forms carbon dioxide... 

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