Df. Deoliveira et Wb. Kover, 1,3-DIPOLAR-CYCLOADDITION OF BENZYLAZIDE TO (-LIMONENE - A PROTECTIONCYCLE FOR THE 8,9-DOUBLE BOND()), Tetrahedron letters, 36(11), 1995, pp. 1799-1802
A method for protecting the 8,9-double bond of (+)-limonene (1) is des
cribed. The key step is the 1,3-dipolar-cycloaddition of benzylazide t
o 1, which affords N-benzyl-N-[9(1-p-menthenylidene)]-amine(2) and N-b
enzyl-N-[8,9-(1-p-menthenylidene)]-amine (3).