C. Kaneko

Syntheses and reactions of 1,2-dihydrocyclobuta[c]isoquinolin-4(3H)-ones☆

Abstract Two-step synthesis of 1,2-dihydrocyclobuta[ c ]isoquinolin-4(3H)-ones, novel cyclobutane-fused heterocycles, from 3-methoxy-2-methylisoquinolin-1(2H)-one and their reacion with olefins are described.

Studies on the n-oxides of π-deficient n-heteroaromatics—XXX1: Photochemistry of acridine 10-oxides (2):2 synthesis and reaction of dibenz[c,f]-1,2-oxazepines

Abstract The dibenz[c,f]-1,2-oxazepines IId and IIe were obtained as the major products from 9-cyano- and 9-chloroacridine 10-oxides (1d and 1e) by irradiation (⩾300 nm) in benzene, and found to undergo a variety of isomerization reactions under mild conditions in the dark. Existence of the same species (IIa-IIc) in the irradiated solution of acridine 10-oxide (1a) and its methylated derivatives (1b and 1c) was also confirmed by UV spectroscopy as well as by some trapping experiments. The direct isolation of IId and IIe not only constitutes the first synthesis of 1,2-oxazepine derivatives but also gives experimental support to the previously suggested mechanism (Chart 1) for the photolyses of acridine 10-oxides and the related N-oxides.

Photocycloaddition of 6-chloro-1,3-dimethyluracil to alkenes: synthesis of 1,2-dihydrocyclobuta[d]pyrimidine-4,6 (3H, 5H)-diones

Abstract The acetone-sensitized photocycloaddition of 6-chloro-1,3-dimethyluracil to alkenes affords directly 1,2-dihydrocyclobuta[ d ]pyrimidine-4,6 (3H, 5H)-diones via 1-chloro-2,4-dimethyl-2,4-diazabichyclo[4.2.0]octa-3,5-diones.

Cycloadditions of 1,2-dihydrocyclobuta[c]quinolin-3 (4H) ones to olefins: new aza-analogues of ortho-quinodimethanes1☆

Abstract An usefulness of 1,2-dihydrocyclobuta[c]quinolin-3 (4) ones as synthons for organic synthesis for aza-analogues of benzocyclobutenes was demonstrated by their inter- and intramolecular cycloadditions to olefins.

Synthesis of desmosterol and epidesmosterol from hyodeoxycholic acid

A new synthesis of desmosterol was described using hyodeoxycholic acid (3alpha,6alpha-dihydroxy-5beta-cholanic acid) as a starting material. Epidesmosterol (3alpha-hydroxycholesta-5,24-diene) was also synthesized for the first time from the same starting material.

A possible oxaziridine intermediate in the photorearrangement reaction of 6-cyanophenanthridine 5-oxide

Abstract Nanosecond spectroscopy and low temperature matrix stabilization technique present evidence of a possible oxaziridine intermediate in the photorearrangement reaction of 6-cyanophenanthridine 5-oxide in ethanol solution to form 5-ethoxyphenanthridine.