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Carbenes acetoxy

SYNTHESIS OF 2-SUBSTITUTED NAPHTHALENEDIOL DERIVATIVES USING CHROMIUM CARBENE COMPLEXES 1-ACETOXY-2-BUTYL-4-METHOXYNAPHTHALENE (1-Naphthalenol, 2-butyl-4-methoxy-, acetate)... [Pg.37]

Nevertheless, acetoxycarbenes are less reactive than analogous chlorocarbenes, as shown by the data in Table 5, where we compare 1,2-H shift rate constants for phenoxymethyl-, cyclobutyl-, and isopropyl halo and acetoxy carbenes. Decreased rates of 1,2-H shifts are observed, due to the influence of the acetoxy spectator substituents, with the kinetic suppression reaching a factor > 900 for the comparison of cyclobutylacetoxycarbene with cyclobutylchlorocar-bene.81... [Pg.89]

In contrast to the cyclopropyl- and cyclobutylhalo- (and acetoxy)carbenes, the cyclopentylhalo- and acetoxycarbenes (91), and their corresponding benzo derivatives, the indanylcarbenes (94), prefer 1,2-H shifts over 1,2-C shifts Eqs. 35 and 36.115 In the absence of strain relief to drive ring expansion, as with the cyclobutylcarbenes, 17, where kc exceeds ku, the 1,2-H shift is preferred.115... [Pg.98]

Synthesis of 2-Substituted Naphthalenediol Derivatives Utilizing Chromium Carbene Complexes l-Acetoxy-2-butyl-4-methoxynaphthalene. J. M. Timko and A. Yamashita, The Upjohn Company,... [Pg.247]

Transient carbene (9) is expected to be a reaction intermediate in the transformation of butadiyne-linked triazene (8) to alkyne-linked bis-2//-indazolcs (10).18 Experimental data and DFT calculations support carbene (9) as an intermediate in this stepwise, non-synchronous coarctate reaction. Methoxy(methylthio)carbene (12) has been observed by UV photoelectron spectroscopy after gas-phase decomposition of oxadiazoline (11).19 The oxadiazoline (13) allows the generation of the acetoxy(methoxy)carbene (14) 20 -pjjg reaC jvj y 0f (he latter with isocyanates has been explored. Such reactions generally yield methyl (acetylamino)oxoacetates (15). DFT calculations permitted interpretation of the experimental data. [Pg.155]

Thermolysis of 2-acetoxy-2-methoxy-5,5-dimethyl-A3-l,3,4-oxadiazoline affords acetoxy(methoxy) carbene.60 The thermal rearrangement of acetoxy(methoxy) car-bene to methyl pyruvate was studied by DFT at the B3PW91/6-31G(d,p) level. The conformation of the carbene was considered, as were competing fragmentations to radical pairs. The authors concluded that the reaction is a concerted 1,2-migration rather than a fragmentation-recombination process. [Pg.141]

Cyclopropan 2-Acetoxy-l-brom-l-chlor- E19b, 1597 (Carben + En)... [Pg.200]

Acetoxy- IV/3, 619 (Baeyer-Villiger-Oxid.) Vl/la, 2, 874 (Baeyer-Villiger-Oxid.) E19b, 198 (Carben -f En)... [Pg.215]

Bicyclo[1.1.0]butan 2,2-Dichlor-3-methoxycarbonyl-1 -methyl-E17e, 77 (H/H Cl/Cl) Cyclopropan 2-Acetoxy-l-(2,2-dichlor-ethenyl)- E19b, 688 (Carben + En)... [Pg.372]

Heptadiensaure 6-Acetoxy-2-methyl- IV/5b, 752 f. 2,4-Hexadiendisaure 2,5-Dimethyl- -dimethylester V/lc, 680 3-Oxa-bicyclo[3.i.O hexan 1-Ethoxy-carbonyl-6,6-dimethyl-2-oxo-E19b, 1089 [(Carben + En (intra)J... [Pg.779]

Bicyclo(4.1.0[heptan 7-Acetoxy-l,7-dimethyl- E17b, 1306 (Br - OAc) Bicyclo 4.3.0jnonan 7-Methoxycar-bonyl- E21d, 3462 [3 (4-SeAr — butanoyloxy)-cyclohexen] Bicyclo 6.1.0 nonan 9-Methoxycar-bonyl-E19b, 1041 (Carben + En) Bicyclo 3.3.0 octan 1-Ethoxycarbo-nyl- VIII, 461 1-Butin... [Pg.926]

Octen (E bzw. Z)-l-Acetoxy-3-methyl- Vl/lb, 533 2-Oxa-bicyclo[4.1.0)heptan 7-(2,2-Dimethyl-propyloxy)-E19b, 1633 (Carben + En)... [Pg.937]

Bicvdo 6.1.0 nonan 9-Ethoxycarbo-nyl-9-fluor- E10 (En + F-C-COOR) E17a, 414 (ArHg-CBrF-COOR + En) E19b, 1044 (Carben + En) 2,6-Octadiene 1 -Acetoxy-3-fluoro-methyl-7-methyl- E10 (OH -> F)... [Pg.1057]

Carbenes are known intermediates in the photodecomposition of diazo-compounds. Insertions of singlet methylene, generated by photoelimination of nitrogen from diazomethane, into 2,3-dimethyl-2,3-epoxybutane and into acetonitrile have been described. Methylene and other photochemically generated carbenes (43) add efficiently to 2-acetoxyacrylonitrile to give the corresponding 1-acetoxy-l-cyanocyclopropanes (44). The formation of methylidyne radicals by irradiation of diazomethane in the presence of hydrogen, however, does not seem to involve an intermediate carbene. ... [Pg.444]

See other pages where Carbenes acetoxy is mentioned: [Pg.67]    [Pg.232]    [Pg.131]    [Pg.173]    [Pg.89]    [Pg.86]    [Pg.255]    [Pg.643]    [Pg.73]    [Pg.256]    [Pg.345]    [Pg.280]    [Pg.254]    [Pg.77]    [Pg.269]    [Pg.287]    [Pg.391]    [Pg.637]    [Pg.650]    [Pg.651]    [Pg.887]    [Pg.278]    [Pg.230]    [Pg.200]    [Pg.1053]    [Pg.715]   
See also in sourсe #XX -- [ Pg.564 ]

See also in sourсe #XX -- [ Pg.564 ]

See also in sourсe #XX -- [ Pg.564 ]

See also in sourсe #XX -- [ Pg.97 , Pg.564 ]



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