The present disclosure provides a styrene derivative and a preparation method thereof, and a modified organic silicone resin and a preparation method and use thereof, and belongs to the technical field of back coating solutions. The styrene derivative is specifically 2,3-difluoro-4-methoxystyrene. A fluorine atom is introduced into a benzene ring structure, and the obtained styrene derivative contains a C—F bond with a relatively high chemical bond energy, such that the styrene derivative has a relatively high thermal stability. The styrene derivative can be introduced into an organic silicone resin to make the obtained modified organic silicone resin have a higher thermal stability. The modified organic silicone resin can be used as a back coating solution to effectively improve a heat resistance of barcode thermal transfer ribbons.

The present disclosure provides a styrene derivative and a preparation method thereof, and a modified organic silicone resin and a preparation method and use thereof, and belongs to the technical field of back coating solutions. The styrene derivative is specifically 2,3-difluoro-4-methoxystyrene. A fluorine atom is introduced into a benzene ring structure, and the obtained styrene derivative contains a C—F bond with a relatively high chemical bond energy, such that the styrene derivative has a relatively high thermal stability. The styrene derivative can be introduced into an organic silicone resin to make the obtained modified organic silicone resin have a higher thermal stability. The modified organic silicone resin can be used as a back coating solution to effectively improve a heat resistance of barcode thermal transfer ribbons.

The present disclosure provides a styrene derivative and a preparation method thereof, and a modified organic silicone resin and a preparation method and use thereof, and belongs to the technical field of back coating solutions. The styrene derivative is specifically 2,3-difluoro-4-methoxystyrene. A fluorine atom is introduced into a benzene ring structure, and the obtained styrene derivative contains a C—F bond with a relatively high chemical bond energy, such that the styrene derivative has a relatively high thermal stability. The styrene derivative can be introduced into an organic silicone resin to make the obtained modified organic silicone resin have a higher thermal stability. The modified organic silicone resin can be used as a back coating solution to effectively improve a heat resistance of barcode thermal transfer ribbons.

The present disclosure provides a styrene derivative and a preparation method thereof, and a modified organic silicone resin and a preparation method and use thereof, and belongs to the technical field of back coating solutions. The styrene derivative is specifically 2,3-difluoro-4-methoxystyrene. A fluorine atom is introduced into a benzene ring structure, and the obtained styrene derivative contains a C—F bond with a relatively high chemical bond energy, such that the styrene derivative has a relatively high thermal stability. The styrene derivative can be introduced into an organic silicone resin to make the obtained modified organic silicone resin have a higher thermal stability. The modified organic silicone resin can be used as a back coating solution to effectively improve a heat resistance of barcode thermal transfer ribbons.

Methods for rapid, efficient, and safe fluoridation and radiolabeling of established and new biomarkers are described. More specifically, the described herein methods may be used for fluoridation of biomarkers or to facilitate isotopic exchanges, especially .sup.19F/.sup.18F IEX, for rapid and efficient manufacturing of radiotracers, including radiotracers for positron emission tomography (PET), under clinically relevant conditions.

Methods for rapid, efficient, and safe fluoridation and radiolabeling of established and new biomarkers are described. More specifically, the described herein methods may be used for fluoridation of biomarkers or to facilitate isotopic exchanges, especially .sup.19F/.sup.18F IEX, for rapid and efficient manufacturing of radiotracers, including radiotracers for positron emission tomography (PET), under clinically relevant conditions.

The present application provides, among other things, compounds and methods for metathesis reactions. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and/or stereoselectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and Z-selectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and E-selectivity. In some embodiments, provided technologies are particularly useful for preparing alkenyl fluorides. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-a. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-b.

The present application provides, among other things, compounds and methods for metathesis reactions. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and/or stereoselectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and Z-selectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and E-selectivity. In some embodiments, provided technologies are particularly useful for preparing alkenyl fluorides. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-a. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-b.

Provided are: a composition for forming a hole transporting layer for perovskite solar cells, which is inexpensive and does not need to be used together with a dopant; and a compound which can be contained in a composition for forming a hole transporting layer. A compound represented by general formula (I) (wherein Ar represents an aryl group; A represents a structure represented by formula (II); Z's independently represent a hydrogen atom, a structure represented by general formula (III), or a structure represented by formula (IV), and maybe the same as or different from each other, wherein a case where each of Z's is a hydrogen atom is excluded; Y's independently represents at least one member selected from the group mentioned below; R.sup.1 and R.sup.2 independently represents a hydrogen atom, an alkyl group or an alkoxy group, or R.sup.1 and R.sup.2 may together form a ring having one or two oxygen atoms; ×'s independently represent an alkyl group, an alkoxy group, an alkylthio group, a monoalkylamino group or a dialkylamino group each of which may be substituted by a halogen atom; k represents 0 or 1; l represents 2 or 3; m represents an integer of 1 to 6; and r represents 1 or 2; wherein, when k is 0, 1 is 3, m is 1 and all of three bonds of A are bonded to Z.

##STR00001##

Provided are: a composition for forming a hole transporting layer for perovskite solar cells, which is inexpensive and does not need to be used together with a dopant; and a compound which can be contained in a composition for forming a hole transporting layer. A compound represented by general formula (I) (wherein Ar represents an aryl group; A represents a structure represented by formula (II); Z's independently represent a hydrogen atom, a structure represented by general formula (III), or a structure represented by formula (IV), and maybe the same as or different from each other, wherein a case where each of Z's is a hydrogen atom is excluded; Y's independently represents at least one member selected from the group mentioned below; R.sup.1 and R.sup.2 independently represents a hydrogen atom, an alkyl group or an alkoxy group, or R.sup.1 and R.sup.2 may together form a ring having one or two oxygen atoms; ×'s independently represent an alkyl group, an alkoxy group, an alkylthio group, a monoalkylamino group or a dialkylamino group each of which may be substituted by a halogen atom; k represents 0 or 1; l represents 2 or 3; m represents an integer of 1 to 6; and r represents 1 or 2; wherein, when k is 0, 1 is 3, m is 1 and all of three bonds of A are bonded to Z.

##STR00001##