KOt-Bu/DMF promoted intramolecular addition of diarylmethanols to imines was developed. A series of 2,3-disubstituted indoles was obtained in good yields. A reaction mechanism of radical cyclization and subsequent dehydration is proposed.

H/D exchanges of arylmethyl amines and nitrogen heterocycles were conveniently achieved with KOt-Bu/DMSO-d6. The method is also applicable for phenyl benzyl ethers, diarylmethanes, and alkyl arenes. These H/D exchange reactions are suggested to proceed via a free radical pathway.

The KOt-Bu promoted homocoupling and decomposition of N′-aryl acylhydrazines has been achieved. The method allows for a novel and efficient synthesis of unsymmetric N′,N′-diaryl acylhydrazines under mild reaction conditions. The reaction probably proceeds via the generation of N′-centered acylhydrazine radicals and the subsequent homolytic aromatic substitution.

Direct addition of tetrahydroisoquinoline derived amides to arylalkenes has been achieved in the presence of KOt-Bu/DMF. Both intermolecular and intramolecular reactions could occur in good yields. α-Amido alkyl radicals are proposed to be generated under the reaction conditions. The reaction is efficient for the synthesis of seven-membered nitrogen heterocycles. A homoprotoberberine was prepared conveniently via this method.

An organocatalytic cascade Michael/Michael reaction between curcumins and 2-arylidene-1,3-indandiones has been studied. Prolinol, chiral thiourea-tertiary amines, and cinchona alkaloids were evaluated as catalysts. Quinine was identified as the best catalyst for the transformation. Multicyclic spiro-1,3-indandiones were prepared in moderate to excellent yields, diastereoselectivities, and enantioselectivities.3-Cinnamoyl-2,6-diphenylspiro[cyclohexane-1,2′-indene]-1′,3′,4-trioneC35H26O4[α]D20=+17.4 (c 0.23, CH2Cl2)Source of chirality: asymmetric synthesis2-(2-Chlorophenyl)-3-cinnamoyl-6-phenylspiro[cyclohexane-1,2′-indene]-1′,3′,4-trioneC35H25ClO4[α]D20=+24.2 (c 0.48, CH2Cl2)Source of chirality: asymmetric synthesis2-(3-Chlorophenyl)-3-cinnamoyl-6-phenylspiro[cyclohexane-1,2′-indene]-1′,3′,4-trioneC35H25ClO4[α]D20=+34.1 (c 0.64, CH2Cl2)Source of chirality: Asymmetric synthesis2-(4-Chlorophenyl)-3-cinnamoyl-6-phenylspiro[cyclo-hexane-1,2′-indene]-1′,3′,4-trioneC35H25ClO4[α]D20=+38.3 (c 0.42, CH2Cl2)Source of chirality: Asymmetric synthesis3-Cinnamoyl-2-(4-fluorophenyl)-6-phenylspiro[cyclo-hexane-1,2′-indene]-1′,3′,4-trioneC35H25FO4[α]D20=+5.7 (c 0.14, CH2Cl2)Source of chirality: asymmetric synthesis2-(4-Bromophenyl)-3-cinnamoyl-6-phenylspiro[cyclo-hexane-1,2′-indene]-1′,3′,4-trioneC35H25BrO4[α]D20=+48.3 (c 0.48, CH2Cl2)Source of chirality: asymmetric synthesis3-Cinnamoyl-2-(2-methoxyphenyl)-6-phenylspiro[cyclo-hexane-1,2′-indene]-1′,3′,4-trioneC36H28O5[α]D20=+29.4 (c 0.66, CH2Cl2)Source of chirality: Asymmetric synthesis3-Cinnamoyl-2-(4-methoxyphenyl)-6-phenylspiro[cyclo-hexane-1,2′-indene]-1′,3′,4-trioneC36H28O5[α]D20=+52.5 (c 0.56, CH2Cl2)Source of chirality: Asymmetric synthesis3-Cinnamoyl-2-(2,5-dimethoxyphenyl)-6-phenylspiro[cyclohexane-1,2′-indene]-1′,3′,4-trioneC37H30O6[α]D20=+99.3 (c 0.30, CH2Cl2)Source of chirality: Asymmetric synthesis3-Cinnamoyl-6-phenyl-2-(thiophen-2-yl)spiro[cyclo-hexane-1,2′-indene]-1′,3′,4-trioneC33H24O4S[α]D20=+31.3 (c 0.46, CH2Cl2)Source of chirality: Asymmetric synthesis6-(2-Chlorophenyl)-3-(3-(2-chlorophenyl)acryloyl)-2-phenylspiro[cyclohexane-1,2′-indene]-1′,3′,4-trioneC35H24Cl2O4[α]D20=+27.5 (c 0.24, CH2Cl2)Source of chirality: Asymmetric synthesis6-(4-Chlorophenyl)-3-(3-(4-chlorophenyl)acryloyl)-2-phenylspiro[cyclohexane-1,2′-indene]-1′,3′,4-trioneC35H24Cl2O4[α]D20=+24.2 (c 0.26, CH2Cl2)Source of chirality: Asymmetric synthesis6-(4-Methoxyphenyl)-3-(3-(4-methoxyphenyl)acryloyl)-2-phenylspiro[cyclohexane-1,2′-indene]-1′,3′,4-trioneC37H30O6[α]D20=+57.5 (c 0.64, CH2Cl2)Source of chirality: Asymmetric synthesis

KOt-Bu/DMF promoted intramolecular addition of diarylmethanols to imines was developed. A series of 2,3-disubstituted indoles was obtained in good yields. A reaction mechanism of radical cyclization and subsequent dehydration is proposed.

A facile synthesis of quinolinones through intramolecular addition of diarylmethanols to α,β-unsaturated amides promoted by KOt-Bu/DMF is reported. A series of 3,4-disubstituted quinolinones were obtained in moderate to good yields. A reaction pathway via the ketyl radical is proposed.