Using a combination of Kumada, Suzuki and Biellmann chemistry, various menaquinones can synthesised rapidly and with stereochemical integrity offering a new way of preparing these vitamin K2 components for the pharmaceutical market. In one embodiment a process for the preparation of a compound of formula (I)

##STR00001## is defined including a step in which (i) a compound of formula (II) is reacted with a compound of formula (III)

##STR00002## wherein R is an alkyl group; LG is a leaving group; m is an integer from 0 to 8; n is an integer of from 0 to 9; and X is hydrogen, halide, hydroxyl or protected hydroxyl; in the presence of a copper, nickel or palladium catalyst.

Using a combination of Kumada, Suzuki and Biellmann chemistry, various menaquinones can synthesised rapidly and with stereochemical integrity offering a new way of preparing these vitamin K2 components for the pharmaceutical market. In one embodiment a process for the preparation of a compound of formula (I)

##STR00001## is defined including a step in which (i) a compound of formula (II) is reacted with a compound of formula (III)

##STR00002## wherein R is an alkyl group; LG is a leaving group; m is an integer from 0 to 8; n is an integer of from 0 to 9; and X is hydrogen, halide, hydroxyl or protected hydroxyl; in the presence of a copper, nickel or palladium catalyst.

Using a combination of Kumada, Suzuki and Biellmann chemistry, various menaquinones can synthesised rapidly and with stereochemical integrity offering a new way of preparing these vitamin K2 components for the pharmaceutical market. In one embodiment a process for the preparation of a compound of formula (I)

##STR00001## is defined including a step in which (i) a compound of formula (II) is reacted with a compound of formula (III)

##STR00002## wherein R is an alkyl group; LG is a leaving group; m is an integer from 0 to 8; n is an integer of from 0 to 9; and X is hydrogen, halide, hydroxyl or protected hydroxyl; in the presence of a copper, nickel or palladium catalyst.

To provide a novel fluorine-containing compound that does not include any long chain perfluoroalkyl unit having 8 or more carbon atoms, which is problematic in terms of the environment, and that is excellent in water repellency/oil repellency, and a surface modifier using the compound. [Solution] There are used a fluorine-containing compound represented by the following general formula (1), the following general formula (2) or the following general formula (5): Rf.sup.1—(CR.sup.1═CR.sup.2—X—Rf.sup.2).sub.n—Y—Z (1), Rf.sup.1—(X—CR.sup.1═CR.sup.2—Rf.sup.2).sub.n—Y—Z (2) or Rf.sup.3—(CF═CR.sup.3—CR.sup.4═CF—Rf.sup.4).sub.n—Y—Z (5); and a surface modifier using the compound.

To provide a novel fluorine-containing compound that does not include any long chain perfluoroalkyl unit having 8 or more carbon atoms, which is problematic in terms of the environment, and that is excellent in water repellency/oil repellency, and a surface modifier using the compound. [Solution] There are used a fluorine-containing compound represented by the following general formula (1), the following general formula (2) or the following general formula (5): Rf.sup.1—(CR.sup.1═CR.sup.2—X—Rf.sup.2).sub.n—Y—Z (1), Rf.sup.1—(X—CR.sup.1═CR.sup.2—Rf.sup.2).sub.n—Y—Z (2) or Rf.sup.3—(CF═CR.sup.3—CR.sup.4═CF—Rf.sup.4).sub.n—Y—Z (5); and a surface modifier using the compound.

Provided are a fluorine-containing ether compound, fluorine-containing ether composition and coating liquid that can form a surface layer having excellent durability, an article having a surface layer that has excellent durability, and a compound that is useful as a raw material of a fluorine-containing ether compound. The fluorine-containing ether compound is represented by the following formula (A1) or formula (A2):

R.sup.f—O—(R.sup.f1O).sub.m—R.sup.f2[—R.sup.1—C(—R.sup.2-T).sub.a(—R.sup.3).sub.3-a].sub.b  Formula (A1)

[(T-R.sup.2—).sub.a(R.sup.3—).sub.3-aC—R.sup.1—].sub.bR.sup.f2—O—(R.sup.f1O).sub.m—R.sup.f2[—R.sup.1—C(—R.sup.2-T).sub.a(-R.sup.3).sub.3-a].sub.b   Formula (A2) wherein each of the reference signs in the formulas are as described in the specification.

Provided are a fluorine-containing ether compound, fluorine-containing ether composition and coating liquid that can form a surface layer having excellent durability, an article having a surface layer that has excellent durability, and a compound that is useful as a raw material of a fluorine-containing ether compound. The fluorine-containing ether compound is represented by the following formula (A1) or formula (A2):

R.sup.f—O—(R.sup.f1O).sub.m—R.sup.f2[—R.sup.1—C(—R.sup.2-T).sub.a(—R.sup.3).sub.3-a].sub.b  Formula (A1)

[(T-R.sup.2—).sub.a(R.sup.3—).sub.3-aC—R.sup.1—].sub.bR.sup.f2—O—(R.sup.f1O).sub.m—R.sup.f2[—R.sup.1—C(—R.sup.2-T).sub.a(-R.sup.3).sub.3-a].sub.b   Formula (A2) wherein each of the reference signs in the formulas are as described in the specification.

A plasma etching method according to an embodiment is a method for etching a silicon-containing film by using plasma of a fluorocarbon gas. The fluorocarbon gas includes at least one selected from a first fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and double bond alternately joined, a second fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and triple bond alternately joined, and a third fluorocarbon which has a main chain of five or more carbons bonded in a linear manner, the main chain having a structure which includes double bond and triple bond.

A plasma etching method according to an embodiment is a method for etching a silicon-containing film by using plasma of a fluorocarbon gas. The fluorocarbon gas includes at least one selected from a first fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and double bond alternately joined, a second fluorocarbon which has a main chain of six or more carbons bonded in a linear manner, the main chain having a structure of single bond and triple bond alternately joined, and a third fluorocarbon which has a main chain of five or more carbons bonded in a linear manner, the main chain having a structure which includes double bond and triple bond.

Using a combination of Kumada, Suzuki and Biellmann chemistry, various menaquinones can synthesized rapidly and with stereochemical integrity offering a new way of preparing these vitamin K2 components for the pharmaceutical market. In one embodiment a process for the preparation of a compound of formula (I) ##STR00001## is defined including a step in which (i) a compound of formula (II) is reacted with a compound of formula (III) ##STR00002## wherein R is an alkyl group; LG is a leaving group; m is an integer from 0 to 8; n is an integer of from 0 to 9; and X is hydrogen, halide, hydroxyl or protected hydroxyl; in the presence of a copper, nickel or palladium catalyst.