ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Benzolactones and Benzocarbocycles by Ring Enlargement of Benzocycloalkenone DerivativesThe Michael adducts 5-8 of benzonitrocycloalkenones 1-4 and acrylaldehyde are converted with (CH3)2 Ti(iPrO)2 or NaCNBH3 to secondary and primary alcohols, 9-12 and 13-16, respectively. These alcohols react under basic conditions to form ring-enlarged benzonitrolactones and benzooxolactones (Scheme 1). The configuration of the bicyclic intermediates in this enlargement step is discussed. The Michael reactions of benzonitrocycloalkenones with methyl vinyl ketone lead to oxoalkyl-benzonitrocycloalkenones 35--38. These products rearrange in the presence of t-BuOK to yield benzonitrocycloalkenones 42, 44, and 46, enlarged by two C-atoms, or tricyclic hydroxy compounds 39, 41, 43, and 45 (Scheme 4).
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19870700823
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