Peterson reagent

Excess Peterson reagent 1606 a reacts with methyl benzoate, via the intermediates 1609 and 1610, to give, on work-up, some a-trimethylsilylacetophenone 1609 and 49% phenylallylsilane 1611 [15], whereas with 1606a ethyl cyclohexanecarboxylate affords only the a-trimethylsilyl-ketone 1612 [16, 17] (Scheme 10.6). 

In a recent synthesis of (-i-)-discodermolide, Nozaki-Hiyama reaction of the aldehyde 1617 with the unsaturated Peterson reagent 1618 then treatment with KH in THE gave the diene 1619 in 74% yield [19] (Scheme 10.8). 

Grignard reagent.80 Competition by nucleophilic aromatic substitution was not observed unless the only active position(s) was (were) substituted with a leaving group, as in the reaction of l-methoxy-2-nitro-naphthalene which gave 1 -alkyl-2-nitronaphthalenes in 73-95% yields.81 The use of Me3SiCH2MgCl (Peterson reagent) provides an entry to nitro-substituted benzyl anion intermediates, as shown in the example of Scheme 9.82... 

Johnson and Tait prepared a trimethylsilylmethylcerium reagent and examined its reaction with carbonyl ctxnpounds. The reagent adds to aldehydes and ketones including many readily enolizable ones to afford 2-hydroxysilanes. This modified Peterson reagent gives vastly superior yields in c< npari-son with trimethylsilylmethyllithium. An example is shown in Scheme 9. 

Table 5 The Addition of the Cerium Peterson Reagent to Acid Chlorides to Form Allylsilanes ...

The reaction has been extended to a-silyl lactones and lactams. Other stabilizing groups have been demonstrated to be effective. For example, the Peterson reagent formed from bis(trimethylsilyl)propyne (357) and that formed from a-silyl acetonitrile derivatives (358) both give the (Z)-alkene as the predominant product (equation 84). ... 

The Peterson methodology has seen wide application in the synthesis of carbohydrates. The preparation of 3-C-methylene sugars (6) was demonstrated by Carey and coworkers, with the methylenation proceeding without elimination of the anomeric alkoxy group (equation 3). A more recent example of Peterson methylenation of a carbohydrate is the synthesis of a deoxyamino sugar (8) by Fraser-Reid (equation 4). In this case, the carbonyl failed to react with the methylenetriphenylphosphorane at room temperature, and forcing conditions resulted in decomposition. Application of the Oshima-Takai-Lom-bardo method also failed. The Peterson reagent added in excellent yield, and the elimination resulted in the formation of the desired methylene (8a) as well as the vinylsilane (8b). 

Bis(silyl)propyne. Reaction of (1) with sUylating agents affords l,3-bis(silyl)propynes, valuable Peterson reagents (eq 16). ... 

The development of a Peterson reagent, (f-BuO)Ph2SiCH2CN, for the preparation of (Z) -P-monosubstituted-a,y8-unsaturated cyanides 95/96 has... 

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