ISSN:0018-019X    

DOI:10.1002/hlca.19710540702

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractThe photolysis of cyclic ketones from C9to C16has been carried out, and formation of cyclobutanols observed in only C11to C16. Although in the mass spectrometer cyclobutanols are not formed, an initial transfer of a γ‐hydrogen atom to the carbonyl group is shown to occur in the mass spectra of all cyclic ketones higher than C

ISSN:0018-019X    

DOI:10.1002/hlca.19710540703

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractThe odor principle β‐damascenone and its isomer α‐damascenone have been prepared by treatment of the corresponding ethyl safranates with excess allyl lithium followed by alkoxide catalyzed isomerization of the resulting products with β, γ‐unsaturated ketonic side chains. Addition of allyltriphenylphosphorane (preferably prepared from allyltriphenylphosphonium chloride) rather than the propenyl isomer to ethyl α‐isopropylidene‐acetoacetate produced ethyl α‐safranate. This represents a new, potentially general method for the synthesis of functionalize

ISSN:0018-019X    

DOI:10.1002/hlca.19710540704

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractThe 6Rconfiguration of (+)‐cis‐γ‐irone [(+)‐4] was established by chemical correlation with (—)‐camphor. (+)‐cis‐γ‐irone [(+)‐4] was converted into (+)‐cis‐α‐irone [(+)‐1], (−)‐trans‐α‐irone [(minus;;)‐2], and (+)‐β‐irone [(+)‐3], which therefore also have the 6Rconfiguration. The 2Sconfigurations of (+)‐cis‐α‐irone [(+)‐1] and (+)‐trans‐α‐irone [(+)‐2] were determined by comparison of their circular dichroism with that ofR‐α‐ionone [(+)‐5]. The 2Sconfiguration of (+)‐cis‐γ‐ir

ISSN:0018-019X    

DOI:10.1002/hlca.19710540705

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractThe sodium salts of the tricyclic tosylhydrazones1, 4and5yield by base‐catalyzed fragmentation between 130–160° the monocyclic ring expansion products2, 3and6.IR.‐spectrometry suggests a diazoalkaneAas the principal intermediate of the fragmentation. Besides the known carbene mechanism the reaction is considered to pass through a noncarbenoid interm

ISSN:0018-019X    

DOI:10.1002/hlca.19710540706

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractThe enantiomers of 7‐hydroxy‐dihydrocitronellal have been prepared stereo‐specifically from (+)‐pulegone by a sequence of analogous reactions. The olfactory properties of the final products and of the intermediates have been investigated. In most cases they exhibit remarkable qualitative and quantitative differences i

ISSN:0018-019X    

DOI:10.1002/hlca.19710540707

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractThe diastereoisomeres ofp‐menthone‐8‐thiol, derived from (+)‐menthol, are the first ketothiols of the terpene series to have been found in nature. Stereochemistry, methods of preparation and olfactory properties of the new compounds are de

ISSN:0018-019X    

DOI:10.1002/hlca.19710540708

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractUnder the conditions of theWhartonreaction, the (±)‐epoxy‐γ‐dihydroionones2and3are transformed into the allylic alcohols4–10. γ‐Damascols4, 5and8were oxidised tocis‐ andtrans‐γ‐damascone12and13. Alternatively, dehydro‐γ‐damascol18was obtained byWittigrearrangement of butinyl ether17, and converte

ISSN:0018-019X    

DOI:10.1002/hlca.19710540709

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractShort‐path thermolysis of (+)‐isopinocampheol (1) at about 330° in the gas phase yields mainly (—)‐(3S, 4S)‐3, 7‐dimethyl‐octa‐1,6‐dien‐4‐ol (2). Longer heating of2at about 290–330° yields as main products the diastereoisomeric hydroxy‐Δ8‐iridenes3, 4and5in ratios dependent on temperature. Above 400°, formation of 4‐methylpent‐3‐en‐1‐al (7) and 2‐butene (8) predominates. Compounds7and8also appear as the stable final thermolysis products of3, 4and5above 500°. Small quantities of (+)‐iso‐dihydrocarveol (6) always occur as by‐product in the thermolysis of1.Short‐path thermolysis of (—)‐isopinocamphone (13) at about 430° leads, with slight epimerisation, to the three diastereoisomeric oxo‐Δ8‐iridenes15, 18and17via (+)‐(3S)‐3, 7‐dimethylocta‐1, 6‐dien‐4‐one (14). Structure and stereochemist

ISSN:0018-019X    

DOI:10.1002/hlca.19710540710

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY

摘要:

AbstractThe synthesis of yomogi alcohol (2, 5, 5‐trimethylhepta‐3,6‐dien‐2‐ol,2) is described, and experiments directed towards its allylic rearrangement to artemisia alcohol detervatives have been carried out. Acidic reagents open the ring of yomogi alcohol epoxide (16) at with participation of the 6,7‐double‐bond, a shift of the vinyl group results to yield a compound with the santolinyl skeleton. The same reagents are without effect when this double bond reduced. Action of butyllithium of the benzaldehyde acetal (41) of 2, 5‐dimethyl‐4‐vinyl‐2, dihydroxy‐hex‐5‐ene (28), obtained by acid‐catalyzed ring opening of yomogi alcohol epoxide in the presence of benzaldehyde, leads to santolinatriene (42).This vinyl shift is not observed in the case of O‐acetyl yomogi alcohol epoxide (46), from white a compound believed to be an oxetan48(R  COCH3) is formed with concomitent shift of the acetate group. Further unusual reactions of the oxetan are described, and some observation about the epoxidation of sterically hindered allyl alc

ISSN:0018-019X    

DOI:10.1002/hlca.19710540711

出版商:WILEY‐VCH Verlag GmbH    

年代:1971

数据来源: WILEY