Luc Giraud

2,2-Divinyladamantane: a new substrate for the modification of silicon surfaces

Abstract 2,2-Divinyladamantane has been readily obtained in six steps from 2-adamantanone. The key steps were a Wittig-Horner-Emmons reaction, an ortho ester Claisen rearrangement using the microwave heating technique and a selenoxide elimination.

An electron transfer reaction in the imidazo[2,1-b]thiazole series

The C-alkylation reaction of 5-nitro-6-chloromethylimidazo [2,1-b] thiazole by the 2-nitropropane anion is shown to proceed by the S RN 1 mechanism. This mechanism is confirmed by the inhibitory effects of dioxygen, p-dinitrobenzene, cupric chloride and TEMPO

Chemical vapor deposition of diamond growth using a chemical precursor

A nucleation method to form diamond on chemically pretreated silicon (111) surfaces is reported. The nucleation consisted of binding covalently 2,2-divinyladamantane molecules on the silicon substrate. Subsequently, low pressure diamond growth was performed via microwave plasma chemical vapor deposition in a tubular deposition system. The resulting diamond layers presented a good crystallinity and the Raman spectra showed a very sharp peak at 1331 cm−1.

Radical reactions leading to substituted coumarins

Abstract The reaction of 4-hydroxycoumarins with a series of quinonic chlorides under photostimulation was shown to provide an efficient approach to 3-alkylated coumarin derivatives. Alkylation reactions of this type proceeded via an electron transfer mechanism (SRN1).

Unexpected reactivity in naphthoquinone series

Abstract An unexpected reactivity of 2-chloromethyl-3-methyl-1,4-naphthoquinone 1 with primary nitroalkanes in classical SRN1 reaction conditions gives two series of new quinones: dialkyl anthraquinones and C-alkylated naphthoquinones.

Stereoselective hetero-Diels–Alder reactions: structure determination of new xanthenedione derivatives by NMR spectroscopy and x-ray crystallography

The proton and carbon spectra of chromane derivatives were completely assigned by the use of 1H, 13C and 2D NMR spectroscopy, including NOESY and 2D INADEQUATE. The unambiguous configurational assignments of all regioisomers were achieved via 2D NOESY. The structure of the regioisomer 7A was confirmed using x‐ray diffraction.