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This paper investigates the third-order nonlinear optical properties of 4α-(4-tert-butylphenoxy) phthalocyaninato dichlorotin(IV) (α-SnOtBpPc) and 4β-(4-tert-butylphenoxy) phthalocyaninato dichlorotin(IV) (β-SnOtBpPc) in different organic solvents. The third-order susceptibilities of α-SnOtBpPc and β-SnOtBpPc are reported in different solvents, using Z-scan techniques with 10 ns laser pulses at 532 nm. Their nonlinear absorption coefficient and absorption cross sections were also determined. The molecular imaginary components of the second-order hyperpolarizability Im[γ] of α-SnOtBpPc and β-SnOtBpPc were found to be 2.60 × 10–31 and 2.94 × 10–31 esu (tetrahydrofuran), 2.12 × 10–31 and 2.54 × 10–31 esu (chloroform), 3.06 × 10–31 and 2.54 × 10–31 esu (dichloromethane), and 1.27 × 10–31 and 1.50 × 10–31 esu (toluene), respectively. This study found that substitution at the α position has an effect of lowering the two-photon (2PA) cross section value for α-SnOtBpPc compared to that for β-SnOtBpPc, with values...

A novel SnCl4-promoted tandem reaction toward multisubstituted indenes via a sequential C-O bond cleavage/Nazarov cyclization/nucleophilic addition reaction has been developed to afford a series of multisubstituted indenes with an all-carbon quaternary center in moderate to good yields.

Formal [4 + 2] cycloaddition between various 3-ethoxycyclobutanones and allyltrialkylsilanes proceeded to give 3-ethoxy-5-[(trialkylsilyl)methyl]cyclohexan-1-ones by catalysis with tin(VI) chloride. The use of allyl-tert-butyldiphenylsilane induced 1,5-hydride transfer, which gave 2-[3-(tert-butyldiphenylsilyl)propyl]-6-methyltetrahydro-4-pyrones.

The formal [3+2] cycloaddition of 5-methoxy-2-(p-methoxyphenyl)oxazole with 2(S)-(benzyloxy)-propanal and 2(S)- [(tert-butyldimethylsilyl)- oxy]propanal in the presence of tin(IV) chloride gave cis-(4R,5S,1'S)- and trans-(4S,5S,1'S)-5-(1'-alkoxyethyl)-4-(methoxycarbonyl)-2-(p-me- thoxyphenyl)-2-oxazolines with high diastereoselectivity (94 and 92% selectivity, respectively). A similar reaction of 5-methoxy-2-(p-metho- xyphenyl)oxazole with 2,3-di-O-benzyl-D-glyceraldehyde gave methyl cis- (4S,5R,1'R)-2-(p-methoxyphenyl)-5-[1',2'-bis(benzyloxy)ethyl]-2-oxazo- line-4-carboxylate with high diastereoselectivity (>95% selectivity), and the latter was easily converted to biologically important chiral 2-amino-1,3,4,5-tetrol derivatives