摘要:

AbstractAcid catalyzed reaction of cyelododecane‐1,2‐dione VI with dimethyl,3‐ketoglutarate II led to the formation of methyl (E)‐6,7,8,9,10,11,12,13‐octahydro‐3‐(methoxycarbonyl)cyclododeca‐[b]furan‐2‐aeetate IX, presumably formed through the dihydrodihydroxy furan VIII. This dihydrofuran intermediate VIII was shown to be characteristic of the reaction of 2‐substituted carbonyl‐compounds with 11 for both α‐chlorocyclohexanone and α‐chlorocyclopentanone furnished furans XVIa and XX, respectively, when treated with 11. The effect of dihydrodihydroxy‐furan intermediates on the course

ISSN:0022-152X    

DOI:10.1002/jhet.5570140501

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractSeveral allylic isothiuronium salts6have been shown to yield 4‐substituted 2‐amino‐5,6‐dihydro‐4H‐1,3‐thiazines (2; R3= H) and the 2‐phenylimino compound10on exposure to trifluoroacetic acid or trifluoroacetic acid‐stannic chloride. The overall process constitutes a convenient transformation of readily available ketones or aldehydes3into the target hetero‐cycles. The scope and limitations of this approach are discussed in terms of carbenium ion intermediates (7). Whereas this method successfully led to the imidazo[2,l‐b][1,3]thiazine13(93% from12), its application to the synthesis of 2‐amino‐2‐thiazolines (eg.14→15) or imidazo‐[2,1‐b]thiazoles (eg.16→17) was unsuccessful. The 2‐acetylimino derivatives9were found to be useful for

ISSN:0022-152X    

DOI:10.1002/jhet.5570140502

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractHalogenation of a number of 3‐alkoxyisothiazoles, occurring exclusively in the 4‐position, followed by cyanation led to various carboxylic acid, carboxamide and amine derivatives. Subsequent dealkylation provided 4‐substituted‐4‐isothiazoI

ISSN:0022-152X    

DOI:10.1002/jhet.5570140503

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractLes synthéses de deux nouveaux types de composés de structures oxo‐3 thioxo‐5 et dithioxo‐3,5 éthoxycarl)onyl‐6 tétrahydro‐2,3,4,5 triazines‐1,2,4 sont décrites; leur réactivite vis á vis d'agents alkylants et de I'hydr

ISSN:0022-152X    

DOI:10.1002/jhet.5570140504

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

Abstract2‐Amino‐5‐chloro‐α‐phenylbenzylidene hydrazone (1) or its methyl derivative2or acetyl derivative10react with diethylmalonic esters to give the corresponding malonyl derivatives3, 4and8. These esters were hydrolyzed to the acids5and6. Treating 5 with dehydrating agents the mesoionic compound 7‐chloro‐9‐phenyl‐3,3‐diethyl‐3H‐pyrazolo[5,1‐b]quinazolin‐10‐ium‐2‐olate (14) was obtained, while the methyl derivative6afforded the desired 9‐chloro‐2,3,4,5‐tetrahydro‐1‐methyl‐3,3‐diethyl‐7‐phenyl‐1H‐benzo‐1,5,6‐triazonine‐2,4‐dione (17). Some derivatives of these compounds were also described. The structures of the new compounds were confirme

ISSN:0022-152X    

DOI:10.1002/jhet.5570140505

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractEthyl phenylpropiolate reacted with ethyl 3‐pyridylacetate in the presence of sodium ethoxide to give ethyl 3,5‐diphenyl‐4‐carbethoxy‐6‐(3‐pyridyl)salicylate (III). Different derivatives for the product were prepared and their structures were elucidated on the basis of ir an

ISSN:0022-152X    

DOI:10.1002/jhet.5570140506

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractFuroin reacts smoothly with dimethyl acetylenedicarboxylateviaa Michael addition, which is followed by a dihydrofuran ring formation. After elimination of water the previously unknown 2,3‐di(2‐furyl)furan structure is produced. Thenoin gives a side reaction to yield a fumaric acid derivative in addition to the expected 2,3‐di(2‐thienyl)furan. A mechanism for the side reaction is suggested. The reactivities of the prepared new furan structures towards some oxidation, hydrogenation and electrophilic reagents were det

ISSN:0022-152X    

DOI:10.1002/jhet.5570140507

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractL'action des phosphodi‐ ou trihydrazides sur les orthoesters permet, en général, d'obtenir des tétrahydro‐2,3,4,5 tétrazaphosphorines‐1,2,4,5,3. Cependant, dans certains cas, il y a formation de amino‐4 triazaphospholidines‐1,2,4,3. Les tétrazaphosphorines‐1,2,4,5,3 obtenues présentent parfois une prototropie. La présence de cette prototropie se traduit par une orientation de la réaction de certains de ces composés avec le formaldéhyde ou l'acétone. La structure des différents hétérocycles ob

ISSN:0022-152X    

DOI:10.1002/jhet.5570140508

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractThe reaction ofN‐(4‐dimethylaminophenyl)nitrones,1, with hydrogen azide proceeds via three distinct pathways to give a mixture of two tetrazoles,5and9, and a 2‐azido‐4‐dimethyl‐aminoaniline derivative,6. The proportions largely depend on the electron‐withdrawing force resident in the function R attached to nitrone carbon. The formation of 5 constitutes a new synthetic approach to 1,5‐disubstit

ISSN:0022-152X    

DOI:10.1002/jhet.5570140509

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY

摘要:

AbstractPreparations for 2,3‐diphenyl‐ and 2‐benzyI‐3‐phenyl‐Δ3‐1,2,4‐oxadiazolin‐5‐ones (3) and (4) and for 2,5‐diphenyl‐Δ4‐1,2,4‐oxadi

ISSN:0022-152X    

DOI:10.1002/jhet.5570140510

出版商:Wiley‐Blackwell    

年代:1977

数据来源: WILEY