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New “Magic Blue” reagent, namely, the blue solution in F113 (CClF 2 CCl 2 F) containing H-abstracting agent bis[ ω -fluorosulfonylperfluoroalkyl] nitroxide R F N(O )R F 2 and ω -fluorosulfonylperfluoronitrosoalkane spin trap R F NO 3 both generated in the reaction of ω -fluorosulfonylperfluorodiacyl peroxide [FO 2 SCF 2 CF 2 OCF(CF 3 )CF 2 OCF(CF 3 )COO] 2 1 with sodium nitrite in F113 (CClF 2 CCl 2 F) at room temperature, reacted with a series of p -substituted benzaldehydes 4 via regio-selective abstraction of the formyl hydrogen followed by spin trapping of the acyl radical intermediate 5 , thus led to the formation of stable spin adducts ω -fluorosulfonylperfluoroalkyl p -substituted benzoyl nitroxides 6 . The correlation analyses of a N values of nitroxides 6 with various substituent constants disclose that the polar effects are the major factors varying the spin density on the nitroxyl-nitrogen while the effect through spin-delocalization is felt slightly.

Unsymmetrical imidazolidines 10-14, optically active imidazolidines 20-22, and 2,3-dihydro-1H-benzimidazoles 28 and 29 were synthesized in good to excellent yields by Mannich reactions of 1,2-ethanediamines 8a-c, 18a-c, or N-methyl-1,2-benzenediamine (26a) with benzotriazole and formaldehyde, followed by the nucleophilic substitution of the benzotriazolyl group with C-nucleophiles (Grignard reagents, sodium cyanide), an S-nucleophile (benzenethiol), and a P-nucleophile (triethyl phosphite).

4-Benzotriazolylmethyl-2,3,4,5-tetrahydro-1,4-benzothiazepines 5a,b, -1,4-benzoxazepine (12) and -1,4-benzodiazepine (20) are obtained via aluminium chloride mediated intramolecular cyclizations of N,N-bis(1H-1,2,3-benzotriazol-1-ylmethyl)-2-(arylthio)ethan-1-amines 4a,b, -2-(phenoxy)ethan-1-amine (11) and -N-[2-(N′-methylanilino)ethyl]amine (19), respectively. Subsequent nucleophilic substitutions of the benzotriazolyl group in 5a,b, 12 and 20 succeeded with Grignard reagents, triethyl phosphite, sodium borohydride, and a silyl enol ether to give novel 2,3,4,5-tetrahydro-1,4-benzothiazepines 6–9, -1,4-benzoxazepines 13 and 14, and -1,4-benzodiazepines 21–23 in good yields.

N- Benzotriazolylmethyl- N -phenethylamines 5a – 5c and 11a – 11c cyclize in the presence of aluminum chloride to produce 1,2,3,4-tetrahydroisoquinolines 6a – 6c and 12a – 12c (70–89%) via electrophilic attack of a transient iminium cation X on the tethered phenyl ring. The Bt group in 2 - benzotriazolylmethyl-1,2,3,4-tetrahydroisoquinolines 6a – 6b was replaced (i) with hydrogen by sodium borohydride to afford N -methyl-1,2,3,4-tetrahydroisoquinolines 7a – 7b or (ii) by nucleophiles, such as Grignard reagents, a silyl enol ether or triethyl phosphite, to furnish novel N -substituted-1,2,3,4-tetrahydroisoquinolines 13a – 13c , 14 or 15 , respectively. Optically active 3-substituted-1,2,3,4-tetrahydroisoquinolines 12a – 12c were similarly prepared in high yields without racemization.

1-Phenyl-5-(benzotriazol-1-yl)hexahydro-1H-pyrrolo[1,2-a]ĭmidazole (18) and 1-phenyl-5-benzotriazolyloctahydroimidazo[1,2-a]pyridine (27) were readily prepared from succindialdehyde or glutaraldehyde, benzotriazole, and N-phenylethylenediamine. Synthons 18 and 27 reacted with Grignard reagents, allylsilanes, silyl ethers, and triethyl phosphite to produce 1-phenyl-5-substituted-hexahydro-1H-pyrrolo[1,2-a]ĭmidazoles 20a-f, 22, 24a,b, and 25 and 1-phenyl-5-substituted-octahydroimidazo[1, 2-a]pyridines 28a-e, 32, 33a,b, and 34 in good to excellent yields. The configurations of 20, 22, 24, and 25 were determined to be cis isomers by NOE experiment, while the configurations and conformations of 28a-e, 32, 33a,b, and 34 were elucidated by (1)H-(1)H COSY and (1)H-(13)C COSY.

1-Benzotriazolylmethyl-3-propylhexahydropyrimidine (1) and 1,3-bis(1H-1,2,3-benzotriazol-1-ylmethyl)-1,2,3,4-tetrahydroquinazoline (3) were readily prepared by reactions of N-propyl-1,3-propanediamine or 2-aminobenzylamine with benzotriazole and formaldehyde, respectively. Intermediate 1 reacted with alkyl and aryl Grignard reagents to produce N,N'-unsymmetrically substituted hexahydropyrimidines 2a,b in 90 and 92% yields, respectively. Nucleophilic substitutions of 3 with Grignard reagents, allylsilane, and triethyl phosphite gave N,N'-disubstituted 1,2,3,4-tetrahydroquinazolines 4a-f, 5, and 6 in good to excellent yields. Successive treatment of 3 with two different Grignard reagents in one-pot reaction led regiospecifically to N,N'-unsymmetrically substituted tetrahydroquinazoline derivatives 8a,b.

1,5-Disubstituted pyrrolidin-2-ones 18a-g, 19a-h, and 20a-f were synthesized in good to excellent yields via the nucleophilic substitution of 5-(benzotriazol-1-yl)-1-substituted-pyrrolidin-2-ones 9 with allylsilanes, organozinc reagents, and phosphorus compounds. Compounds 9 and 5-(benzotriazol-2-yl)-1-substituted-pyrrolidin-2-one isomers 10 are readily prepared in total 70-84% yields from 2, 5-dimethoxy-2,5-dihydrofuran (7), primary amines 8, and benzotriazole; 9 and 10 react identically with nucleophiles.

N- Benzotriazolylmethyl- N -phenethylamines 5a – 5c and 11a – 11c cyclize in the presence of aluminum chloride to produce 1,2,3,4-tetrahydroisoquinolines 6a – 6c and 12a – 12c (70–89%) via electrophilic attack of a transient iminium cation X on the tethered phenyl ring. The Bt group in 2 - benzotriazolylmethyl-1,2,3,4-tetrahydroisoquinolines 6a – 6b was replaced (i) with hydrogen by sodium borohydride to afford N -methyl-1,2,3,4-tetrahydroisoquinolines 7a – 7b or (ii) by nucleophiles, such as Grignard reagents, a silyl enol ether or triethyl phosphite, to furnish novel N -substituted-1,2,3,4-tetrahydroisoquinolines 13a – 13c , 14 or 15 , respectively. Optically active 3-substituted-1,2,3,4-tetrahydroisoquinolines 12a – 12c were similarly prepared in high yields without racemization.

4-Benzotriazolylmethyl-2,3,4,5-tetrahydro-1,4-benzothiazepines 5a,b, -1,4-benzoxazepine (12) and -1,4-benzodiazepine (20) are obtained via aluminium chloride mediated intramolecular cyclizations of N,N-bis(1H-1,2,3-benzotriazol-1-ylmethyl)-2-(arylthio)ethan-1-amines 4a,b, -2-(phenoxy)ethan-1-amine (11) and -N-[2-(N′-methylanilino)ethyl]amine (19), respectively. Subsequent nucleophilic substitutions of the benzotriazolyl group in 5a,b, 12 and 20 succeeded with Grignard reagents, triethyl phosphite, sodium borohydride, and a silyl enol ether to give novel 2,3,4,5-tetrahydro-1,4-benzothiazepines 6–9, -1,4-benzoxazepines 13 and 14, and -1,4-benzodiazepines 21–23 in good yields.

1-Benzotriazolylmethyl-3-propylhexahydropyrimidine (1) and 1,3-bis(1H-1,2,3-benzotriazol-1-ylmethyl)-1,2,3,4-tetrahydroquinazoline (3) were readily prepared by reactions of N-propyl-1,3-propanediamine or 2-aminobenzylamine with benzotriazole and formaldehyde, respectively. Intermediate 1 reacted with alkyl and aryl Grignard reagents to produce N,N'-unsymmetrically substituted hexahydropyrimidines 2a,b in 90 and 92% yields, respectively. Nucleophilic substitutions of 3 with Grignard reagents, allylsilane, and triethyl phosphite gave N,N'-disubstituted 1,2,3,4-tetrahydroquinazolines 4a-f, 5, and 6 in good to excellent yields. Successive treatment of 3 with two different Grignard reagents in one-pot reaction led regiospecifically to N,N'-unsymmetrically substituted tetrahydroquinazoline derivatives 8a,b.

Condensation of 2-(3-methyl-1H-indol-1-yl)ethylamine (7) with benzotriazole and formaldehyde gave 2-(1H-1,2,3-benzotriazol-1-ylmethyl)-10-methyl-1,2,3,4-tetrahydropyrazino[1,2-a]indole (8) in 96% yield. Nucleophilic substitutions of the benzotriazolyl group in 8 with NaBH(4), NaCN, triethyl phosphite, allylsilanes, silyl enol ether and Grignard reagents afforded novel 10-methyl-1,2,3,4-tetrahydropyrazino[1,2-a]indoles 9a-i in 78-95% yields.

Ethyl (4R)-3-(1H-1,2,3-benzotriazol-1-ylmethyl)-1,3-thiazolane-4-carboxylate (6) and 1-[1,3-benzothiazol-3(2H)-ylmethyl]-1H-1,2,3-benzotriazole (8) were readily prepared by reactions of L-cysteine ethyl ester hydrochloride and 1-aminothiophenol with benzotriazole and formaldehyde, respectively. Chiral thiazolidine esters 7a-c were obtained by reactions of intermediate 6 with organozinc derivatives. Nucleophilic substitutions of 8 with Grignard reagents gave N-substituted dihydrobenzothiazoles 9a-c.

Readily available N-acylbenzotriazoles 2a−q efficiently acylate aqueous ammonia and primary and secondary amines to give primary, secondary, and tertiary amides in good to excellent yields. The wide applicability of the procedure is illustrated by the preparation of (i) α-hydroxyamides from α-hydroxy acids and of (ii) perfluoroalkylated amides.

Readily available N-acylbenzotriazoles 2a-q efficiently acylate aqueous ammonia and primary and secondary amines to give primary, secondary, and tertiary amides in good to excellent yields. The wide applicability of the procedure is illustrated by the preparation of (i) alpha-hydroxyamides from alpha-hydroxy acids and of (ii) perfluoroalkylated amides.

1,5-Disubstituted pyrrolidin-2-ones 18a-g, 19a-h, and 20a-f were synthesized in good to excellent yields via the nucleophilic substitution of 5-(benzotriazol-1-yl)-1-substituted-pyrrolidin-2-ones 9 with allylsilanes, organozinc reagents, and phosphorus compounds. Compounds 9 and 5-(benzotriazol-2-yl)-1-substituted-pyrrolidin-2-one isomers 10 are readily prepared in total 70-84% yields from 2, 5-dimethoxy-2,5-dihydrofuran (7), primary amines 8, and benzotriazole; 9 and 10 react identically with nucleophiles.