Dolbier HW Solutions 486

Dolbier HW Solutions 486 - ethyl acetoacetate 1 Benzyl...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
The necessary alkyl halide in this synthesis is 1-bromo-2-methylbutane. ( d ) Once again disconnection reveals the necessary halide, which is treated with diethyl malonate. Alkylation of diethyl malonate with benzyl bromide is the f rst step in the preparation of 3-phenylpropanoic acid. 21.8 Retrosynthetic analysis of the formation of 3-methyl-2-butanone is carried out in the same way as for other ketones. The two alkylation steps are carried out sequentially. CH 3 CCHCOCH 2 CH 3 NaOCH 2 CH 3 CH 3 Br O O CH 3 CH 3 CCH 2 COCH 2 CH 3 NaOCH 2 CH 3 CH 3 Br O O Ethyl acetoacetate Ethyl 2-methyl-3-oxobutanoate 1. HO 2 , H 2 O 2. H 1 CH 3 CCCOCH 2 CH 3 O O CH 3 H 3 C Ethyl 2,2-dimethyl-3-oxobutanoate CH 3 CCH(CH 3 ) 2 O 3-Methyl-2-butanone 3. heat 2CH 3 X 1 CH 3 CCH 2 2 O O CH 3 CCH CH 3 CH 3 3-Methyl-2-butanone (two disconnections as shown) Derived from
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ethyl acetoacetate 1 Benzyl bromide C 6 H 5 CH 2 Br Diethyl malonate CH 2 (COOCH 2 CH 3 ) 2 NaOCH 2 CH 3 ethanol Diethyl 2-benzylmalonate C 6 H 5 CH 2 CH(COOCH 2 CH 3 ) 2 1. HO 2 , H 2 O 3-Phenylpropanoic acid C 6 H 5 CH 2 CH 2 COH O 2. H 1 3. heat 1 Derived from diethyl malonate CH 2 COH O 2 Required halide C 6 H 5 CH 2 X C 6 H 5 CH 2 O CH 2 COH 1 Diethyl malonate CH 2 (COOCH 2 CH 3 ) 2 NaOCH 2 CH 3 ethanol 1-Bromo-2-methylbutane CH 3 CH 2 CHCH 2 Br CH 3 1. HO 2 , H 2 O 2. H 1 3. heat Diethyl 2-(2-methylbutyl)malonate CH 3 CH 2 CHCH 2 CH(COOCH 2 CH 3 ) 2 CH 3 4-Methylhexanoic acid CH 3 CH 2 CHCH 2 CH 2 COH CH 3 O 580 ESTER ENOLATES...
View Full Document

Ask a homework question - tutors are online