Matches in SemOpenAlex for { <https://semopenalex.org/work/W2950676879> ?p ?o ?g. }
Showing items 1 to 70 of
70
with 100 items per page.
- W2950676879 endingPage "1828" @default.
- W2950676879 startingPage "1826" @default.
- W2950676879 abstract "Recently, synthesis of methylenetetrahydrofurans has received much attention due to their versatile usefulness in organic synthesis. The compounds were prepared most frequently either by the Zn(II)/amine-catalyzed coupling reaction of alkylidenemalonates with propargyl alcohol or Michael addition of propargyl alcohol to alkylidenemalonates followed by a palladium-mediated exo-dig cyclization. Methylenetetrahydrofurans can be used for the synthesis of polysubstituted tetrahydrofurans or furans. However, chemical transformations of these valuable compounds were not reported much. Very recently we reported the synthesis of 2,5-dihydrofuran derivatives by the sequential introduction of propargyl alcohol at the primary position of the Baylis-Hillman adducts, radical cyclization, iodolactonization, and finally decarboxylation strategy (Scheme 1). During the investigations we reasoned that we could prepare 2,4-disubstituted 2,5-dihydrofuran derivative (B) by following the similar protocol from the methylenetetrahydrofuran 3a (Scheme 2). Starting methylenetetrahydrofuran 3a was prepared in 51% yield from the reaction of benzylidenemalonate 1a and propargyl alcohol (2a) in the presence of n-BuLi (1.1 equiv) and CuI (30 mol%) in THF by following the reported method, which described the reaction with propargyl amines instead of propargyl alcohol. With the starting material 3a, we examined the hydrolysis of ester groups. Initially we tried the hydrolysis with LiOH in aq THF at room temperature. From the reaction, we obtained a mixture of starting material 3a and ethyl 2-phenyl-4-methyl-2,5dihydrofuran-3-carboxylate (4a). After many trials we found that the use of excess LiOH (3 equiv) at elevated temperature (50-60 C) gave 5a in good yield (75%) instead" @default.
- W2950676879 created "2019-06-27" @default.
- W2950676879 creator A5010448944 @default.
- W2950676879 creator A5036619471 @default.
- W2950676879 creator A5071260315 @default.
- W2950676879 date "2005-11-20" @default.
- W2950676879 modified "2023-10-16" @default.
- W2950676879 title "Synthesis of 2,3,4-Trisubstituted 2,5-Dihydrofuran Derivatives" @default.
- W2950676879 cites W1980948819 @default.
- W2950676879 cites W1994769979 @default.
- W2950676879 cites W2011180004 @default.
- W2950676879 cites W2016610665 @default.
- W2950676879 cites W2041562277 @default.
- W2950676879 cites W2041833449 @default.
- W2950676879 cites W2054412018 @default.
- W2950676879 cites W2100612460 @default.
- W2950676879 cites W2106966459 @default.
- W2950676879 cites W2158386499 @default.
- W2950676879 cites W2166606943 @default.
- W2950676879 cites W2172390262 @default.
- W2950676879 cites W2179105804 @default.
- W2950676879 cites W2181278378 @default.
- W2950676879 cites W2949568356 @default.
- W2950676879 cites W2950574597 @default.
- W2950676879 cites W2950718477 @default.
- W2950676879 cites W2952140866 @default.
- W2950676879 cites W2952265692 @default.
- W2950676879 cites W2952328220 @default.
- W2950676879 cites W2952419135 @default.
- W2950676879 doi "https://doi.org/10.5012/bkcs.2005.26.11.1826" @default.
- W2950676879 hasPublicationYear "2005" @default.
- W2950676879 type Work @default.
- W2950676879 sameAs 2950676879 @default.
- W2950676879 citedByCount "11" @default.
- W2950676879 countsByYear W29506768792014 @default.
- W2950676879 countsByYear W29506768792016 @default.
- W2950676879 countsByYear W29506768792017 @default.
- W2950676879 countsByYear W29506768792018 @default.
- W2950676879 crossrefType "journal-article" @default.
- W2950676879 hasAuthorship W2950676879A5010448944 @default.
- W2950676879 hasAuthorship W2950676879A5036619471 @default.
- W2950676879 hasAuthorship W2950676879A5071260315 @default.
- W2950676879 hasBestOaLocation W29506768791 @default.
- W2950676879 hasConcept C147597530 @default.
- W2950676879 hasConcept C185592680 @default.
- W2950676879 hasConcept C21951064 @default.
- W2950676879 hasConceptScore W2950676879C147597530 @default.
- W2950676879 hasConceptScore W2950676879C185592680 @default.
- W2950676879 hasConceptScore W2950676879C21951064 @default.
- W2950676879 hasIssue "11" @default.
- W2950676879 hasLocation W29506768791 @default.
- W2950676879 hasOpenAccess W2950676879 @default.
- W2950676879 hasPrimaryLocation W29506768791 @default.
- W2950676879 hasRelatedWork W1814206567 @default.
- W2950676879 hasRelatedWork W2033589463 @default.
- W2950676879 hasRelatedWork W2044634666 @default.
- W2950676879 hasRelatedWork W2057499724 @default.
- W2950676879 hasRelatedWork W2057640882 @default.
- W2950676879 hasRelatedWork W2072777769 @default.
- W2950676879 hasRelatedWork W2330215216 @default.
- W2950676879 hasRelatedWork W2949431091 @default.
- W2950676879 hasRelatedWork W2953125207 @default.
- W2950676879 hasRelatedWork W3045648531 @default.
- W2950676879 hasVolume "26" @default.
- W2950676879 isParatext "false" @default.
- W2950676879 isRetracted "false" @default.
- W2950676879 magId "2950676879" @default.
- W2950676879 workType "article" @default.