The kinetics of the reactions of benzhydryl cations with eight diazo compounds 1 a-g were investigated photometrically in dichloromethane. The nucleophilicity parameters N and slope parameters s of these diazo compounds were derived from the equation log k (20 degrees C)=s (E+N) and compared with the nucleophilicities of other pi systems (alkenes, arenes, silyl enol ethers, silyl ketene acetals...

A series of beta-(N-tosyl)amino diazo carbonyl compounds have been prepared by nucleophilic condensation of N-tosylimines with acyldiazomethanes. The diazo decomposition of these diazo carbonyl compounds under various catalytic conditions, including Rh(II) carboxylates, Cu(I) and Cu(II) complexes, PhCO(2)Ag/Et(3)N, TsOH, and SnCl(2).2H(2)O, has been investigated. It was found that, in most case...

Alkynyl aziridines can be obtained from the catalytic asymmetric aziridination (AZ reaction) of alkynyl imines with diazo compounds in high yields and high asymmetric inductions mediated by a chiral boroxinate or BOROX catalyst. In contrast to the AZ reaction with aryl- and alkyl-substituted imines, alkynyl imines react to give cis-substituted aziridines with both diazo esters and diazo acetami...

The reactions of isolable dialkysilylene 1 with 2-diazo-1,2-diphenylethanone and ethyl 2-diazo-2-phenylacetate gave elusive silacycles, 2H-1,2-oxasiletes 2 and 3, respectively, in high yields. Because these reactions occur at low temperatures of ca.-30 °C, initial complexation of the silylene to the carbonyl oxygen of the diazocarbonyl compounds is suggested to trigger dinitrogen elimination fo...

The synthesis of spirocyclic amide acetals (33–93 %) has been achieved through Ru(II)-catalyzed condensations N-carbamate protected pyrrolidinones with metal carbenes derived from α-diazo-β-ketoesters. Thanks to the mildness diazo decomposition conditions induced by a 1 : combination [CpRu(MeCN)3][BArF] and 1,10-phenanthroline, formation sensitive products is possible. Full characterization thi...

The title crystal structure, C(11)H(18)N(4)O(3), is the first diazo-acetamide in which the diazo-acetyl group is attached to an N atom. The piperazine ring is in a chair form and hence the mol-ecule has an extended conformation. Both ring N atoms are bonded in an essentially planar configuration with the sum of the C-N-C angles being 359.8 (2) and 357.7 (2)°. In the crystal structure, the O ato...

The C-3'-carbonyl group of N-protected spectinomycin is efficiently converted into a diazo group via base treatment of the corresponding tosylhydrazone. The diazo group imparts a new synthetically useful reactivity pattern on the sugar ring of the molecule. The synthesis of C-3'-deoxo-, monohalo- and dihalospectinomycins via the intermediacy of these diazo compounds is described. The reduced bi...