The present invention relates to a process for synthesizing functionalized mercaptans essentially in the absence of oxygen, and also to a composition making it possible in particular to implement this process. Said functionalized mercaptans are of the following formula (I):

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in which, R.sub.1 and R.sub.7, which are identical or different, are a hydrogen atom or an aromatic or nonaromatic, linear, branched or cyclic, saturated or unsaturated, hydrocarbon chain of 1 to 20 carbon atoms which may comprise one or more heteroatoms; X is chosen from -C(=O)-, -CH.sub.2- or -CN; R.sub.2 is: (i) either absent when X represents -CN, (ii) or a hydrogen atom, (iii) or -OR.sub.3, R.sub.3 being a hydrogen atom or an aromatic or nonaromatic, linear, branched or cyclic, saturated or unsaturated, hydrocarbon chain of 1 to 20 carbon atoms which may comprise one or more heteroatoms, (iv) or -NR.sub.4R.sub.5, R.sub.4 and R.sub.5, which are identical or different, being a hydrogen atom or an aromatic or nonaromatic, linear, branched or cyclic, saturated or unsaturated, hydrocarbon chain of 1 to 20 carbon atoms which may comprise one or more heteroatoms; n is equal to 1 or 2; and * represents an asymmetric carbon.

The present invention relates to a process of preparing polyfluoroether compounds with unsaturated end groups and to compounds prepared by said process.

The present invention relates to a process of preparing polyfluoroether compounds with unsaturated end groups and to compounds prepared by said process.

Methods for synthesizing a mercaptan compound include the steps of contacting a nickel-molybdenum catalyst with H.sub.2S at a sulfiding temperature of less than or equal to 235° C. to form a supported sulfur-containing catalyst, and then contacting an alcohol compound or an olefin compound, H.sub.2S, and the supported sulfur-containing catalyst to form a reaction mixture containing the mercaptan compound.

Methods for synthesizing a mercaptan compound include the steps of contacting a nickel-molybdenum catalyst with H.sub.2S at a sulfiding temperature of less than or equal to 235° C. to form a supported sulfur-containing catalyst, and then contacting an alcohol compound or an olefin compound, H.sub.2S, and the supported sulfur-containing catalyst to form a reaction mixture containing the mercaptan compound.

Methods for synthesizing a mercaptan compound include the steps of contacting a nickel-molybdenum catalyst with H.sub.2S at a sulfiding temperature of less than or equal to 235° C. to form a supported sulfur-containing catalyst, and then contacting an alcohol compound or an olefin compound, H.sub.2S, and the supported sulfur-containing catalyst to form a reaction mixture containing the mercaptan compound.

According to one embodiment, in producing polythiols in a manner similar to a conventional method, a polythiol having improved storage stability may be produced in a convenient manner by adjusting reaction conditions so as to prevent thiourea from remaining within products. In particular, the equivalent weight of thiourea to be used in a reaction may be adjusted to a predetermined range, thereby reducing the amount of unreacted thiourea, and thiourea may be removed once more in a sub sequent process, thereby effectively removing remaining thiourea while achieving a high yield. The polythiol thus produced does not contain residual thiourea, and thus does not show discoloration or cloudiness caused by precipitates even under prolonged storage or high-temperature conditions.

According to one embodiment, in producing polythiols in a manner similar to a conventional method, a polythiol having improved storage stability may be produced in a convenient manner by adjusting reaction conditions so as to prevent thiourea from remaining within products. In particular, the equivalent weight of thiourea to be used in a reaction may be adjusted to a predetermined range, thereby reducing the amount of unreacted thiourea, and thiourea may be removed once more in a sub sequent process, thereby effectively removing remaining thiourea while achieving a high yield. The polythiol thus produced does not contain residual thiourea, and thus does not show discoloration or cloudiness caused by precipitates even under prolonged storage or high-temperature conditions.

The present invention discloses processes for producing methyl ethyl sulfide by contacting dimethyl sulfide and diethyl sulfide in the presence of a suitable catalyst. Methyl ethyl sulfide can be used as an odorant in natural gas. Integrated mercaptan and sulfide manufacturing systems and integrated methods for making mercaptans and sulfides also are disclosed.

The present invention discloses processes for producing methyl ethyl sulfide by contacting dimethyl sulfide and diethyl sulfide in the presence of a suitable catalyst. Methyl ethyl sulfide can be used as an odorant in natural gas. Integrated mercaptan and sulfide manufacturing systems and integrated methods for making mercaptans and sulfides also are disclosed.