- Novel pyridine-catalyzed reaction of dimethyl acetylenedicarboxylate with aldehydes and N-tosylimines: Efficient synthesis of 2-benzoylfumarates and 1-azadienes
-
A novel reaction of 1,4-dipolar intermediate 3, generated from pyridine and dimethyl acetylenedicarboxylate, with aromatic aldehydes, resulted in the facile synthesis of 2-benzoylfumarates via the elimination of pyridine, whereas with N-tosylimines as dipolarophiles the reaction afforded highly substituted 1-azadienes. The reaction of pyridine and dimethyl acetylenedicarboxylate with N-substituted isatins, resulted in a novel three component condensation, affording spiropyrido[2,1-b][1,3]oxazino derivatives in high yields via 1,4-dipolar cycloaddition.
- Nair, Vijay,Sreekanth,Abhilash,Biju,Rema Devi,Menon, Rajeev S.,Rath, Nigam P.,Srinivas
-
-
Read Online
- Poly(4-vinylpyridine-co-ethylvinylbenzene) as heterogeneous reusable catalyst for the synthesis of benzoyl fumarate
-
Poly(4-vinylpyridine-co-ethylvinylbenzene) 25 % cross-linked (with divinylbenzene) has been found to be an effective heterogeneous catalyst for the synthesis of benzoyl fumarate from aldehyde and dimethyl acetylenedicarboxylate. Various aromatic aldehydes undergo this reaction with good yield in presence of 15 wt% of the catalyst. The catalyst was recovered and reused six times without appreciable alteration in activity.
- Kashyap, Bishwapran,Phukan, Prodeep
-
p. 797 - 800
(2016/03/23)
-
- Nicotinic acid functionalized organomodified silica as an efficient heterogeneous catalyst for the synthesis of benzoyl fumarate
-
A new hybrid catalyst has been developed by incorporating nicotinic acid onto an organomodified silica. The catalyst was applied as a heterogeneous catalyst for the synthesis of benzoyl fumarate. The reactions work well in the presence of 20 wt % of the catalyst at room temperature to produce the desired products in high yield. The catalyst could be recovered and reused without appreciable change in activity.
- Singh, Rana Sanjay Kumar,Kashyap, Bishwapran,Phukan, Prodeep
-
supporting information
p. 6687 - 6690
(2013/11/19)
-
- A new ferrocene-based bulky pyridine as an efficient reusable homogeneous catalyst
-
An effective approach to reusing a homogeneous catalyst has been demonstrated. A ferrocene-based bulky pyridine has been synthesized and utilized as a homogeneous catalyst for the synthesis of benzoylfumarates as well as for acetylation. After the reaction, the catalyst was separated by simple precipitation and reused without appreciable loss of activity. The Royal Society of Chemistry 2013.
- Kashyap, Bishwapran,Phukan, Prodeep
-
p. 15327 - 15336
(2013/09/02)
-
- Reactions of Arylaldehydes and N-Sulfonated Imines with Dimethyl Acetylenedicarboxylate Catalyzed by Nitrogen and Phosphine Lewis Bases
-
(Equation presented) In the reaction of arylaldehydes or N-sulfonated imines (0.5 mmol) with dimethyl acetylenedicarboxylate (DMAD) (0.6 mmol) catalyzed by pyridine or DMAP (20 mol %), we found that (E)-2-aryl-but-2- enedioic acid dimethyl ester 1 or (E)-2-[aryl-(toluene-4-sulfonylimino)methyl]- but-2-enedioic acid dimethyl ester 2 was formed in good yields at 60°C in THF. A plausible mechanism has been proposed.
- Li, Chao-Qun,Shi, Min
-
p. 4273 - 4276
(2007/10/03)
-
- Photosensitized oxidation of furans; Part 18: A simple method for a one-pot synthesis of functionalized methyl cis-4-oxoalk-2-enoates
-
Functionalized methyl cis-4-oxoalk-2-enoates 2 are synthesized in a one-pot procedure by singlet oxygen oxygenation of the corresponding 2-methoxyfurans 1 in methanol and reduction of the resulting hydroperoxides 4 and 5 by the sulfides 6 which are selectively oxidized into the sulfoxides 7. The synthetic method has a wide range of applicability and affords compounds 2 stereoselectively and in good yields; concomitantly the sulfoxides 7 are obtained in excellent yields.
- Iesce,Cermola,Piazza,Scarpati,Graziano
-
p. 439 - 443
(2007/10/02)
-
- Photosensitized oxidation of furans; part 17: A simple method for the synthesis of 5-hydroperoxyfuran-2(5H)-ones
-
The 5-hydroperoxyfuran-2(5H)-ones 3 are synthesized by acid hydrolysis of the dihydrofurans 1 which are prepared in one-pot procedure by reaction of the corresponding furans 4 with singlet oxygen and methanol. The synthetic method has a wide range of applicability; however, compounds 3 unsubstituted at C-4 cannot be prepared since the corresponding dihydrofurans 1 are not formed.
- Iesce,Cermola,Graziano,Scarpati
-
p. 944 - 948
(2007/10/02)
-
- Photosensitized Oxidation of Furans. Part 16. Selective Formation and Chemical Properties of 3H-1,2-Dioxoles: a New Class of Cyclic Peroxides
-
Direct evidence is provided for the selective formation of the 3H-1,2-dioxoles 1 by thermal conversion of the furan endo-peroxides 2 substituted at C-1 with an alkoxy substituent and at C-5 with an electron-withdrawing group.The thermally unstable dioxole
- Iesce, M. Rosaria,Cermola, Flavio,Graziano, M. Liliana,Cimminiello, Guido,Scarpati, Rachele
-
p. 1855 - 1858
(2007/10/02)
-
- Photosensitized Oxidation of Furans. Part 14. Nature of Intermediates in Thermal Rearrangement of Some endo-Peroxides of 2-Alkoxyfurans: New Rearrangement Pathway of Furan endo-Peroxides
-
2-Methoxy-5-phenylfurans (1a-c) substituted at C-4 with electron-withdrawing groups, by dye-sensitized photo-oxygenation in non-participating solvents, give the endo-peroxides (3a-c) which by thermal rearrangement partly yield the 3H-1,2-dioxoles (14a-c).The latter, which are the first examples of this ring system, are thermally very unstable.Their formation can be deduced only from the products obtained by thermal rearragement which are structurally related with the thermal rearrangement products of 3H-1,2,4-dioxazoles (10).The behavior of the furans (1a-c) contrasts with that of the 2-methoxy-5-phenylfurans unsubstituted at C-4 which under the same conditions give carbonyl oxides.
- Graziano, M. Liliana,Iesce, M. Rosaria,Cimminiello, Guido,Scarpati, Rachele
-
p. 241 - 245
(2007/10/02)
-