Treatment of 4-heptafluoroisopropyl-2-methoxy-3,5,6-trifluropyridine (4 ) with aqueous ammonia in THF gave 2-amino-3,5-difluoro-4-heptafluoroisopropyl- 6-methoxy pyridine (5) in 7 1% yield. Chlorination of this amine with 'ButOCl at -16°C gave an unstable product, namely 2-dichloroarnino-3,5- difluoro-4-heptafluoroisopropyl-6-methoxy pyridine (6). Iodine-catalysed rearrangement of this dic...

This paper describes the use of a substituent effects study to understand the mechanistic basis for an interfacial Diels-Alder reaction that does not proceed with standard second-order kinetics. Cyclopentadiene (Cp) undergoes a Diels-Alder reaction with a chemisorbed mercaptobenzoquinone to yield an immobilized Diels-Alder adduct. The pseudo-first-order rate constants are not linearly related t...

DFT calculations (B3LYP/LANL2DZ/6-31 G*) were used to investigate the ways in which 1-methyl-4-phenyl-1-azabuta-1,3-diene and 4-phenyl-1-oxabuta-1,3-diene bind to a Fe(CO)(4) moiety. As possible coordination modes, eta(2)-coordination across the C=C or C=N/C=O bond, sigma-coordination to the lone pair of the heteroatom, or eta(3)-coordination through the C=C-C or the N=C-C/O=C-C moiety were con...

the mononuclear complex [cu(l)(ch3cn)(pph3)]clo4, (1), (l= 2,5-diphenyl-3,4-bis(2-pyridyl)cyclopenta-2,4-dien-1-one), has been synthesized and investigated by elemental analysis, ir, 1h nmr, uv-vis spectroscopic methods and x-ray diffraction. the complex crystallizes in the non-centrosymmetric space group p212121 in accord with the asymmetric (atropisomer) cu centre. its coordination polyhedron...

The tin(IV)-catalyzed reaction of β-nitrostyrene with (E)-3-methyl-1,3-pentadiene in toluene afforded two major nitronic ester cycloadducts in 27% and 29% yield that arise from the reaction at the less substituted diene double bond. Also present were four cycloadducts from the reaction at the higher substituted diene double bond, two of which were the formal cycloadducts of (Z)-3-methyl-1,3-pen...

A novel and rapid approach to chiral mono- or di-substituted spiroketals based on remote asymmetric induction by intramolecular iodoetherification of ene or diene ketals has been developed. This strategy concisely offers 5,5- and 5,6-spiroketals including the natural insect pheromone of the wasp.

A convenient synthesis of (6R,7S)-(+)-himachala-9,11-diene, the pheromone of the chrysomelid beetle Phyllotreta striolata is described. The diene is obtained in a single operation by a spontaneous “bromination/dehydrobromination” of 2,6,6,9-tetramethylbicyclo[5.4.0]undec-8-ene. The halogenation/dehalogenation sequence proceeds spontaneously in CCl4, and is less uniform in CH2Cl2 and CHCl3. H NM...

Two new lignans (R,Z)-3-(3,4-dimethoxybenzyl)-2-(3, 4-dimethoxybenzylidene)-gamma-butyrolactone (1) and (2R, 3S)-2-acetoxy-2,3-bis(3,4-dimethoxybenzyl)-gamma-butyrolactone (2), and four new polyacetylenes, (2Z,8E,10E)-heptadeca-2,8,10-triene-4, 6-diyn-1-ol (3), (2E,9Z)-octadeca-2,9-diene-4,6-diyne-1,18-diol (4), (2E,9Z)-18-hydroxy-octadeca-2,9-diene-4,6-diyn-1-yl acetate (5), and (2E,9Z)-1-hydr...

The enzymatic hydrolysis of meso-1,7-diacetoxy-2,6-dimethylheptane 5, prepared from 2,6-dimethylhepta-1,6-diene 6, gave the (2S,6R)-7-acetoxy-2,6-dimethyl-1-heptanol 1, which was transformed to the (2R,6R)-2,6,10-trimethyl-1-undecanol 7. In this manner, the C14 side chain of a-Tocopherol was synthesized from 2,6-dimethylhepta-1,6-diene 6 in only 5 steps.