A NOVEL FREE RADICAL REARRANGEMENT

The reaction of benzyloxyethanol with carbon tetrabromide was investigated, and a possible mechanism was proposed.     

A NOVEL ACETYLENIC ESTER-VINYL ETHER REARRANGEMENT

A novel acetylenic ester-vinyl ether rearrrangement takes place when perfluoroacetylenicester is subject to hydrolysis with aqueous sodium hydroxide. The rearrangement is highlystereoselective and the Z-isomer predominates to the extent of above 94% in all cases. Thecrossover experiments showed that this rearrangement proceeds predominately intramolecu-larly. By using ~(18)O labeling technique and on the basis of mass spectral study, it wasshown that the rearrangement most likely roceeds through an intramolecular 1, 3 shiftof the methoxy group to the β-carbon atom. A novel mechanism involving a cage reactionin the organic phase of a two-phase system is proposed.     

THE REARRANGEMENT REACTION of 3-ALKYLPHTHALIDES

ＴＨＥＲＥＡＲＲＡＮＧＥＭＥＮＴＲＥＡＣＴＩＯＮｏｆ３－ＡＬＫＹＬＰＨＴＨＡＬＩＤＥＳ￥ＳＵＨｕａＰＡＮＧ；ＸｉａｏＴｉａｎＬＩＡＮＧ；ＺｏｎｇＲｕＧＵＯ；ＧｕａｎｇＺｈｏｎｇＹＡＮＧ（ＩｎｓｔｉｔｕｔｅｏｆＭａｔｅｒｉａＭｅｄｉｃａ，Ｃｈｉｎｅｓｅ...     

CHEMISTRY OF DENUDATINE Ⅲ. REARRANGEMENT OF DENUDATINE

Treatment of denudatine 1 with 10％ HCl soln. at 30-40℃ for 1 day leads to another rearrangement product 3 along with a pair of epimers 2A and 2B. Upon adding a little EtOH in the reaction solution, only a pair of epimers 4A and 4B were obtained along with the unchanged starting material.     

COPE REARRANGEMENT INVOLVING CARBON—CARBON BOND CLEAVAGE

A new type of Cope rearrangement involving carbon-carbon bond cleavage (or de-tbutylation) was found during the heating of 4-allyl-4-methyl-2, 6-di-t-butylsemiquinone,     

ZIRCONIA-SUPPORTED BORIA CATAL YST FOR BECKMANN REARRANGEMENT OF CYCL OHEXANONE OXIME

ＺＩＲＣＯＮＩＡ┐ＳＵＰＰＯＲＴＥＤＢＯＲＩＡＣＡＴＡＬＹＳＴＦＯＲＢＥＣＫＭＡＮＮＲＥＡＲＲＡＮＧＥＭＥＮＴＯＦＣＹＣＬＯＨＥＸＡＮＯＮＥＯＸＩＭＥＣｈｅｎｇＳｈｉｂｉａｏ，ＸｕＢｏｑｉｎｇ，ＪｉａｎｇＳｈａｎ，ＣａｉＴｉａｎｘｉ，ＷａｎｇＸｉａｎ...     

CHEMISTRY OF DENUDATINE. I. A NOVEL REARRANGEMENT OF DENUDATINE

Treatment of denudatine 1 with 10% HCl soln. at 45-50℃ for 3 days leads to a pair of epimers 4A and 4B, Structures of 4A and 4B have been elucidated on the basis of chemical and spectral methods.     

SYNTHESES OF ETHYL PERFLUOROACETYLENIC ESTERS AND STEREOCHEMISTRY OF A NOVEL ACETYLENIC ESTER-VINYL ETHER REARRANGEMENT

The intramolecular Wittig reaction has been applied to the syntheses of ethyl trifluoro-but-2-ynoate (2a) and ethyl heptafluoro-hex-2-ynoate (2b). Treatment of 2a and 2b withaqueous sodium hydroxide, followed by acidification, affords 3-ethoxy-4,4,4-trifluoro-2-bu-tenoic acid (3a) and 3-ethoxy-4,4,5,5,6,6,6-heptafluoro-2-hexenoic acid (3b) respectively. Anovel acetylenic ester to vinyl ether rearrangement takes place as thc corresponding methylestors. Their structures are ascertained by elemental analysis and IR and NMR spectra.The stereochemistry of this novel acetylenic ester to vinyl ether rearrangement has been studied.On the basis of ~1H NMR data, we find that the reaction is highly stereoseleetive and the Z-isomer predominated to the extent of above 94% in all cases. The results of the solventeffect of benzene and NOE enhancement in NMR spectroscopy further confirm the configura-tion of the Z- and E-isomer.     

CHEMISTRY OF DENUDATINE.Ⅳ.AN UNUSUAL REARRANGEMENT BY CONTRACTION OF RING C IN DENUDATINE AND DIACETYLDENUDATINE

An unusual rearrangement by contraction of the ring C in denudatine 1 and di-acetyldenudatine 2 is presented.     

THERMAL THIONO－THIOLO REARRANGEMENT OF O－ARYL－O－METRYL－O－PROPARGYL THIONOPHOSPHATES

ＴＨＥＲＭＡＬ　ＴＨＩＯＮＯ－ＴＨＩＯＬＯ　ＲＥＡＲＲＡＮＧＥＭＥＮＴ　ＯＦ　Ｏ－ＡＲＹＬ－Ｏ－ＭＥＴＲＹＬ－Ｏ－ＰＲＯＰＡＲＧＹＬ　ＴＨＩＯＮＯＰＨＯＳＰＨＡＴＥＳＷｅｉＢｉｎＣＨＥＮ；ＦｅｎｇＬｉｎｇＹＡＮＧ；ＺｈａｏＪｉｅＬＩＵ（Ｉｎｓｔｉｔｕ...     

STEREOCHEMISTRY OF THE BENZILIC ACID-TYPE REARRANGEMENT IN BASE-CATALYZED AUTOXIDATION OF 3α,5-CYCLO-5α-CHOLESTANE-6-ONE

The configuration of the hydroxy acid 2, a product from base-catalyzedautoxidation of 3α,5-cyclo-5α-cholestane-6-one,was established on the basis of NMRtechniques and the mechanism of the formation of 2 was discussed.     

STUDY ON THE REARRANGEMENT REACTION OF 5－AMINO－1－AMINOCARBONYL－1，2，AND ITS ANALOGUES

ＳＴＵＤＹＯＮＴＨＥＲＥＡＲＲＡＮＧＥＭＥＮＴＲＥＡＣＴＩＯＮＯＦ５－ＡＭＩＮＯ－１－ＡＭＩＮＯＣＡＲＢＯＮＹＬ－１，２，ＡＮＤＩＴＳＡＮＡＬＯＧＵＥＳ￥ＲｏｎｇＪｉａｎＬＵ；ＨｕａＺｈｅｎｇＹＡＮＧ；ＢａｏＹｉｎｇＱＩＡＮ；ＨａｉＹａｎＤＥＮＧ（Ｎ...     

THE REARRANGEMENT OF 1,7β-DIMETHYL-7α-HYDROXY-8aα-CARBOXYMETHYL-9β-CARBOMETHOXY-4bα, 5, 6, 7, 8, 8a-HEXAttYDROFLUORENE LACTONE INDUCED BY DIBAL-H

1,7β- Dimethyl-7α- hydroxy-8aα-carboxymethyl-9β-carbomethoxy-4bα, 5, 6, 7, 8, 8α-hexahydrofluorene lactone(2) is converted to 8, 12-epoxyallogibberic acid methyl ester(4) by the action of diisobutyl aluminum hydride (DIBAL-H) with a novel rearrangement reaction.