Abstract
The regioselective N1-alkylation of 3,4-dihydropyrimidin-2(1H )-ones via Mitsunobu reaction is reported.
Using the highly reactive Mitsunobu coupling reagent combination N ,N ,N ′,N ′-tetramethylazodicarboxamide/tributylphosphine
(TMAD-TBP) and a set of primary alcohols a small library
of N1-alkylated dihydropyrimidones is obtained in good to excellent
yields.
Key words
Mitsunobu reaction - selective alkylations - amides - dihydropyrimidones - Biginelli condensation
References
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Typical Experimental
Procedure (Outlined for Entry 5): In a dry 5 mL reaction vial
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After cooling to r.t. benzyl alcohol (54 mg, 0.50 mmol, 52 µL),
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Hz, 1 H), 7.06 (d, J = 7.0 Hz,
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