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Synthesis of α-allenic aldehydes and allenyl trimethylsilyl ketones via (trimethylsilyloxy)butatrienes

✍ Scribed by R.G. Visser; L. Brandsma; H.J.T. Bos

Publisher
Elsevier Science
Year
1981
Tongue
French
Weight
128 KB
Volume
22
Category
Article
ISSN
0040-4039

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✦ Synopsis

a-Lithiated (trimethylsilyloxy)butatrienes, generated by 1,4-elimination of methanol from l-trimethylsilyloxy-4-methoxy-2-alkynes with :=rt-butyllithium, give mixtures of cr-allenic aldehydes and allenyl trimethylsilyl ketones which can be separated by distillation. The ratio aldehyde/ketone is solvent dependent. Previous work from our laboratory ly2 has resulted in practical syntheses of cumulenic ethers R1R2C=C=C=CH-0-alkyl.

As only a few3-5 synthesis of a-allenic aldehydes have been

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