ISSN:0165-0513    

DOI:10.1002/recl.19861050702

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe reaction of acetyl hypofluorite in acetic acid with both cyclohexane and cyclohexene has been investigated. Analysis by GCMS and radio‐HPLC, using18F as a tracer, revealed that, apart from typical products expected from a radical reaction, several compounds originating from carbocationic intermediates were formed. On the basis of the observed products, a single‐electrontransfer (SET) mechanism leading to an intermediate radical‐cation is pro

ISSN:0165-0513    

DOI:10.1002/recl.19861050703

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractHydroxy‐dechlorination,\documentclass{article}\usepackage{amsmath}\pagestyle{empty}\begin{document}$ {\rm ZC}_6 {\rm H}_4 {\rm Cl} + ^ \bullet{\rm OH}\xrightarrow{{(9)}}{\rm ZC}_6 {\rm H}_4 {\rm OH} + {\rm Cl}^ \bullet $\end{document}is advanced as a straightforward process enabling measurement of structural effects on rates of addition of\documentclass{article}\pagestyle{empty}\begin{document}$ ^ \bullet {\rm OH} $\end{document}to substituted benzenes. Hydroxyl radicals were generated fromtert‐butyl hydroperoxide. Under the conditions employed (gas phase, 290°C), reaction (9) with chlorobenzene is 0.3 times as fast as H abstraction to giveo/m/p‐\documentclass{article}\pagestyle{empty}\begin{document}$ {\rm ClC}_6 {\rm H}_4 ^ \bullet $\end{document}radicals. Analogousipsosubstitution of methyl was not observed; withp‐chlorotoluene,\documentclass{article}\pagestyle{empty}\begin{document}$ ^ \bullet {\rm OH} $\end{document}forms\documentclass{article}\pagestyle{empty}\begin{document}$ {\rm ClC}_6 {\rm H}_4 {\rm CH}_2 ^ \bullet $\end{document}at least 30 times faster than it gives reaction (9); witho‐ andp‐ClC6H4CF3(2c), both reaction 9 and displacement of CF3to give ClC6H4OH (reaction 12) occur, the latteripsosubstitution beingca.19 times faster witho‐ than withp‐2c. A thermokinetic rationale is given, for what is apparently a steric effect. Site selectivities for reaction (9), expressed as isomer distributiono/m/p, are: 55/25/20 for Z = Cl and 54/31/15 for

ISSN:0165-0513    

DOI:10.1002/recl.19861050704

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19861050705

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractMethylenecyclobutane and higher alkylidenecyclobutanes containingno substituents in the ringundergoCriegeeozonolysis with formation of cyclobutanone as a major product. When thering contains α‐substituents, a primary ozonide is formed in which the (substituted) cyclobutyl ring is ruptured simultaneously with O‐O fission. The overall result is a rearrangement to a seven‐membered cyclic 3,4‐dioxa ketone (cf.Scheme 3). This rearrangement is mechanistically related to previously studied cyclopropyl systems in which the small ring is ruptured without the assistance of a ring substituent.At room temperature, the 3,4‐dioxacycloheptanone derivative slowly loses formaldehyde, leaving a γ;‐butyrolactone. Structurally related 3,4‐dioxacyclohexanones are relatively stable,i.e.they do not decompose into correspon

ISSN:0165-0513    

DOI:10.1002/recl.19861050706

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractEasily accessible 1,6‐anhydro‐3,4‐isopropylidene‐β‐D‐galactopyranose has been converted in four steps (i.e., oxidation, reduction, triflation andWaldeninversion with lithium azide or potassium phthalimide) into 1,6‐anhydro‐2‐azido‐ or ‐2‐phthalimido‐2‐deoxy‐3,4‐O‐isopropylidene‐β‐D‐galacto‐ pyranose. The 2‐azido derivative, obtained after acidolysis of the isopropylidene group, could be coupled regioselectively at the hydroxyl group at C‐4 with either 1,3,4,6‐tetra‐O‐acetyl‐2‐phthalimido‐2‐deoxy‐β‐D‐ glucopyranose or 3,4,6‐tri‐O‐acetyl‐2‐phthalimido‐2‐deoxy‐α‐D‐glucopyranosyl bromide in the presence of the soluble cataly

ISSN:0165-0513    

DOI:10.1002/recl.19861050707

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19861050708

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractPhotolysis of the aryl maleates la,b produces homolysis of the carbonyl‐aryloxy bond, followed by internal addition of the acyl radical to the neighbouring carbonyl group, giving the unexpected products 3 or 4; by contrast the aryl fumarates 2a,b follow the “normal” photo‐Fries

ISSN:0165-0513    

DOI:10.1002/recl.19861050709

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe structure of the title compound, C21H25N3O3, was determined by X‐ray analysis. Mr=367.45; orthorhombic; Space group: P21212121; Z=4; a=10.3727 (7), b=11.7659(20), c=15.4711(17) Å, V=1888.16 Å3, D =1.29 Mg/m3. CuKα radiation, graphite crystal monochromator, γ;=1.5418, μ(CuKα)=6.70 cm−1, F(000)=784.00, T=290°K. Final conventional R‐factor=0.0364, RW=0.0396 for 3435 unique reflections and 345 variables. The structure was solved with MULTAN. The absolute configuration wa

ISSN:0165-0513    

DOI:10.1002/recl.19861050710

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe structure of the title compound, C32H35N3O6S, was determined by X‐ray analysis. Mr=589.71; triclinic; Space group: P‐1; Z=2; a=11.1173(7), b=12.0068(13), c=13.1270(8)Å, α=104.612(8), β=103.833(5), γ=109.706(6)°, γ;=1491.80Å3, DC=1.31 Mg/m3. CuKα radiation, graphite crystal monochromator, λ=1.5418, μ(CuKα) = 13.27 cm−1, F(000)=620.00, T=290°K. Final conventional R‐factor=0.0428, RW=0.0463 for 3099 unique reflections and 519 variables. The structure was solved usin

ISSN:0165-0513    

DOI:10.1002/recl.19861050711

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY