Reaction of ynolate anions derived from silylketenes with electrophiles: a facile preparation of silyl ynol ethers and functionalized silylketenes

Abstract

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Ketene organoelement derivatives. Synthesis of bis(l-R-2-oxovinyl)silanes and germanes (R = SiMe3, GeMe3, SnMe3)

“…For instance, the reaction of compound 6b with 2 equiv. of benzylamine in hexane gives N,N´ diben zyl 2,2´ (dimethylsilylene)bis[2 (trimethylgermyl)acet amide] (14) in good yield (Scheme 4).…”

“…N,N´ Dibenzyl 2,2´ (dimethylsilylene)bis[2 (trimethylger myl)acetamide] (14). Benzylamine (0.43 g, 4 mmol) was added to a solution of compound 6b (0.5 g, 1.3 mmol) in hexane (20 mL) with stirring.…”

Ynolate anions

“…3 tert-Butyldimethylsilylketene 7b can also be employed. 4 The reaction conditions seem to be critical since when other bases are used, or BuLi is added at 278 °C, the yield of the corresponding disilylketenes decreases to less than 30%.…”

“…3). Ynolates bearing a phenyl 1 or silyl substituent 4 give b-lactones after protonation. However, ynolates bearing an alkyl (primary, secondary or tertiary) substituent react with aldehydes to afford 2 : 1 adducts 36 in good to moderate yields 14,16 since the corresponding b-lactone enolates are more reactive than the ynolates themselves.…”

Ynolates as Functional Carbanions

“…The intermediate 105 is trapped with Co 2 (CO) 8 to give cobalt clusters (see Section 3). Kita reported that the soft silyl chlorides like Ph 3 SiCl afforded silyl ketenes 6. Disilyl ynol ethers, prepared from ynolate dianions, rearrange to disilylketenes mediated by salts 23.…”