A flame-retardant vanillin-derived small molecule, a process for forming a flame-retardant polymer, and an article of manufacture comprising a material that contains the flame-retardant vanillin-derived small molecule are disclosed. The flame-retardant vanillin-derived small molecule can be synthesized from vanillin obtained from a bio-based source, and can have at least one phosphoryl or phosphonyl moiety with phenyl, allyl, or thioether substituents. The process for forming the flame-retardant polymer can include reacting a diol vanillin derivative and a flame-retardant phosphorus-based molecule to form the flame-retardant vanillin-derived small molecule, and binding the flame-retardant vanillin-derived small molecule to a polymer. The material in the article of manufacture can be flame-retardant, and contain the flame-retardant vanillin-derived small molecules. Examples of materials that can be in the article of manufacture can include resins, plastics, adhesives, polymers, etc.

A flame-retardant vanillin-derived small molecule, a process for forming a flame-retardant polymer, and an article of manufacture comprising a material that contains the flame-retardant vanillin-derived small molecule are disclosed. The flame-retardant vanillin-derived small molecule can be synthesized from vanillin obtained from a bio-based source, and can have at least one phosphoryl or phosphonyl moiety with phenyl, allyl, or thioether substituents. The process for forming the flame-retardant polymer can include reacting a diol vanillin derivative and a flame-retardant phosphorus-based molecule to form the flame-retardant vanillin-derived small molecule, and binding the flame-retardant vanillin-derived small molecule to a polymer. The material in the article of manufacture can be flame-retardant, and contain the flame-retardant vanillin-derived small molecules. Examples of materials that can be in the article of manufacture can include resins, plastics, adhesives, polymers, etc.

A flame-retardant vanillin-derived cross-linker, a process for forming a flame-retardant polymer, and an article of manufacture comprising a material that contains the flame-retardant vanillin-derived cross-linker are disclosed. The flame-retardant vanillin-derived cross-linker can be synthesized from vanillin obtained from a bio-based source, and can have at least one phosphoryl or phosphonyl moiety with phenyl, allyl, epoxide, propylene carbonate, or thioether substituents. The process for forming the flame-retardant polymer can include reacting a diol vanillin derivative and a flame-retardant phosphorus-based molecule to form the flame-retardant vanillin-derived cross-linker, and binding the flame-retardant vanillin-derived cross-linker to a polymer. The material in the article of manufacture can be flame-retardant, and contain flame-retardant vanillin-derived cross-linkers. Examples of materials that can be in the article of manufacture can include resins, plastics, adhesives, polymers, etc.

A flame-retardant vanillin-derived cross-linker, a process for forming a flame-retardant polymer, and an article of manufacture comprising a material that contains the flame-retardant vanillin-derived cross-linker are disclosed. The flame-retardant vanillin-derived cross-linker can be synthesized from vanillin obtained from a bio-based source, and can have at least one phosphoryl or phosphonyl moiety with phenyl, allyl, epoxide, propylene carbonate, or thioether substituents. The process for forming the flame-retardant polymer can include reacting a diol vanillin derivative and a flame-retardant phosphorus-based molecule to form the flame-retardant vanillin-derived cross-linker, and binding the flame-retardant vanillin-derived cross-linker to a polymer. The material in the article of manufacture can be flame-retardant, and contain flame-retardant vanillin-derived cross-linkers. Examples of materials that can be in the article of manufacture can include resins, plastics, adhesives, polymers, etc.

A flame-retardant vanillin-derived molecule, a process for forming a flame-retardant resin, and an article of manufacture comprising a material that contains the flame-retardant vanillin-derived molecule are disclosed. The flame-retardant vanillin-derived molecule can be synthesized from vanillin obtained from a bio-based source, and can have at least one phosphoryl or phosphonyl moiety with phenyl, allyl, epoxide, propylene carbonate, or thioether substituents. The process for forming the flame-retardant resin can include reacting a vanillin derivative and a flame-retardant phosphorus-based molecule to form the flame-retardant vanillin-derived molecule, and binding the flame-retardant vanillin-derived molecule to a resin. The flame-retardant vanillin-derived molecules can also be bound to polymers. The material in the article of manufacture can be flame-retardant, and contain the flame-retardant vanillin-derived molecules. Examples of materials that can be in the article of manufacture can include resins, plastics, adhesives, polymers, etc.

A flame-retardant vanillin-derived molecule, a process for forming a flame-retardant resin, and an article of manufacture comprising a material that contains the flame-retardant vanillin-derived molecule are disclosed. The flame-retardant vanillin-derived molecule can be synthesized from vanillin obtained from a bio-based source, and can have at least one phosphoryl or phosphonyl moiety with phenyl, allyl, epoxide, propylene carbonate, or thioether substituents. The process for forming the flame-retardant resin can include reacting a vanillin derivative and a flame-retardant phosphorus-based molecule to form the flame-retardant vanillin-derived molecule, and binding the flame-retardant vanillin-derived molecule to a resin. The flame-retardant vanillin-derived molecules can also be bound to polymers. The material in the article of manufacture can be flame-retardant, and contain the flame-retardant vanillin-derived molecules. Examples of materials that can be in the article of manufacture can include resins, plastics, adhesives, polymers, etc.

An object of the present invention is to provide a bisphosphite compound giving higher selectivity for the target product with maintaining a high reaction rate. The present invention relates to a dihydroxybiphenyl compound represented by the following formula (1) and a bisphosphite compound represented by the following formula (2):

##STR00001##

wherein in formulae (1) and (2), each of R.sup.1 to R.sup.4, R.sup.11 to R.sup.14, and Z.sup.1 to Z.sup.4 is the same as defined in the description.

An object of the present invention is to provide a bisphosphite compound giving higher selectivity for the target product with maintaining a high reaction rate. The present invention relates to a dihydroxybiphenyl compound represented by the following formula (1) and a bisphosphite compound represented by the following formula (2):

##STR00001##

wherein in formulae (1) and (2), each of R.sup.1 to R.sup.4, R.sup.11 to R.sup.14, and Z.sup.1 to Z.sup.4 is the same as defined in the description.

A lithium secondary battery includes a positive electrode; a negative electrode; and an electrolyte disposed between the positive electrode and the negative electrode, wherein the positive electrode includes a positive active material represented by Formula 1, and the electrolyte includes a lithium salt; a non-aqueous solvent; and a phosphite compound represented by Formula 2, wherein the phosphite compound is present in amount of about 0.1 wt % to about 5 wt % based on a total weight of the electrolyte:
Li.sub.xNi.sub.yM.sub.1-yO.sub.2-zA.sub.zFormula 1 ##STR00001## wherein, in Formula 1, 0.9x1.2, 0.7y0.98, and 0z<0.2; M comprises Al, Mg, Mn, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, Nb, Mo, Sr, Sb, W, Bi, or a combination thereof; and A is an element having an oxidation number of 1 or 2; wherein in Formula 2, R.sub.1 to R.sub.3 are independently an unsubstituted C.sub.1-C.sub.30 alkyl group or an unsubstituted C.sub.6-C.sub.60 aryl group.

A lithium secondary battery includes a positive electrode; a negative electrode; and an electrolyte disposed between the positive electrode and the negative electrode, wherein the positive electrode includes a positive active material represented by Formula 1, and the electrolyte includes a lithium salt; a non-aqueous solvent; and a phosphite compound represented by Formula 2, wherein the phosphite compound is present in amount of about 0.1 wt % to about 5 wt % based on a total weight of the electrolyte:
Li.sub.xNi.sub.yM.sub.1-yO.sub.2-zA.sub.zFormula 1 ##STR00001## wherein, in Formula 1, 0.9x1.2, 0.7y0.98, and 0z<0.2; M comprises Al, Mg, Mn, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, Nb, Mo, Sr, Sb, W, Bi, or a combination thereof; and A is an element having an oxidation number of 1 or 2; wherein in Formula 2, R.sub.1 to R.sub.3 are independently an unsubstituted C.sub.1-C.sub.30 alkyl group or an unsubstituted C.sub.6-C.sub.60 aryl group.