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Re-examination of the methylenation reaction Pt 1

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Rhodium:
Cupric Oxide as an Efficient Catalyst in Methylenation of Catechols
Masao Tomita and Yoshiaki Aoyagi
Chem. Pharm. Bull. 16(3) 523-526 (1968) (https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylenation.cuo.html)

Abstract
Methylenation of catechols with methylene halides was found to be catalyzed more effectively by cupric oxide in dimethylformamide.
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The Synthesis of 3,4-Dihydroxy-2-Methoxybenzaldehyde: The use of Methylenedioxy as a Protecting Group
I. R. C. Bick and R. A. Russell
Aust. J. Chem. 22, 1563-1568 (1969) (https://www.thevespiary.org/rhodium/Rhodium/pdf/2-meo-piperonal.cuo.methylenation.pdf)

Rhodium:
Preparation and Properties of Naphtho[1,2-d]- and Naphtho[2,3-d]-1,3-dioxolen
Franz Dallacker, Ralf Morcinek und Arafat Rabic
Z. Naturforsch. 34b, 1434–1442 (1979) (https://www.thevespiary.org/rhodium/Rhodium/pdf/dallacker.md-naphtalenes.pdf)

Summary
We describe the preparation of unsubstituted 1a, of 4-methoxy- (1b), and of  5-methoxynaphtho[1,2-d]-1,3-dioxole (1c). Treatment of 1a with bromine leads to 5-bromo-naphtho-[1,2-d]-1,3-dioxole (1d). The carboxylic acid 1f and 5-methyl-thio-naphtho[1,2-d]-1,3-dioxole (1g) are prepared by bromine-lithium-exchange  from 1d. Formylation yielding 1i and bromination yielding 1h show that 4-methoxy-naphtho[1,2-d]-1,3-dioxole can easily undergo electrophilic substitution.

Because of less SE-reactivity of 1c the carboxylic acid 1l and methyl-thio-naphtho[1,2-d]-1,3-dioxole (1n) can only be prepared from the lithium-compound as intermediate. Naphtho[2,3-d]-1,3-dioxole (2a) can easily undergo electrophilic substitution, showed by nitration yielding 2b, acetylation yielding 2c, bromination yielding 2d and 2e. The carboxylic acid 2j, the methyl-derivative 2k, the thionaphthole 2l, and the aldehyde 2m are prepared from the lithium-compound of 2d.

Treating 2e with n-butyl-lithium leads to the dilithium-naphthyl derivative, a suitable starting material to obtain the dimethyl-compound 2n, the dicarboxylic acid 2o, and the dialdehyde 2p. Monomethyl-thio- (2q) and dimethyl-thio-naphtho[2,3-d]-1,3-dioxole (2r) are prepared in the same manner.

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