Methods for producing and purifying organotin compounds, suppressing formation of dialkyl tin compounds, and selectively removing tetrakis(dialkylamino) tin compounds

A method of synthesizing a monoalkyl tin triamide compound having formula (1) and containing no detectable amount of a dialkyl tin diamide compound having formula (2):

• wherein R1 and R1′ are each independently a primary alkyl group having about 1 to about 10 carbon atoms or a secondary alkyl group having about 3 to about 10 carbon atoms, the method comprising:
• (a) lithiating a dialkylamine in a solution containing a first solvent to produce a lithium dialkylamide having a concentration in the solution of up to about 10 wt %;
• (b) preparing a premix solution comprising tetrachlorotin and an alkyltrichloro tin compound R1SnCl3 in a second solvent, wherein an amount of the tetrachlorotin in the premix solution is about 0.1 to about 5 mol % relative to the amount of the alkyl trichlorotin compound;
• (c) adding the premix solution to the lithium dimethylamide at about −10° C. to about 10° C. to produce a reaction mixture, wherein the amount of lithium dimethylamide in the reaction mixture is at least about 3.09 equivalents relative to the amount of the alkyl trichlorotin compound;
• (d) removing the LiCl salt product by filtration;
• and
• (e) removing the first solvent and the second solvent under vacuum to produce a product containing the monoalkyl tin triamide having formula (1) and no detectable amount of the dialkyl tin diamide compound having formula (2).

A method of synthesizing a monoalkyl tin triamide compound having formula (1) and containing no detectable amount of a dialkyl tin diamide compound having formula (2):

• wherein R1 and R1′ are each independently a primary alkyl group having about 1 to about 10 carbon atoms or a secondary alkyl group having about 3 to about 10 carbon atoms, the method comprising:
• (a) lithiating a dialkylamine in a solution containing a first solvent to produce a lithium dimethylamide having a concentration in the solution of up to about 10 wt %;
• (b) adding a solution of tetrachlorotin in a second solvent to the lithium dialkylamide at about −15° C. to about 0° C. to produce a reaction mixture containing about 0.3% to about 2 mol % tetrakis(dialkylamino)tin relative to an amount of the lithium dialkylamide;
• (c) adding a solution of an alkyl trichlorotin compound R1SnCl3 in a third solvent to the reaction mixture at about −15° C. to about 10° C., wherein the amount of lithium dimethylamide in the reaction mixture is at least about 3.09 equivalents relative to the amount of the alkyl trichlorotin compound and wherein the amount of tetrachlorotin in the reaction mixture is about 0.1 mol % to about 5 mol % relative to the amount of the alkyl trichlorotin compound;
• (d) removing the LiCl salt product by filtration;
• and
• (e) removing the first solvent, the second solvent, and the third solvent under vacuum to produce a product containing the monoalkyl tin triamide having formula (1) and no detectable amount of the dialkyl tin diamide compound having formula (2).

A method of synthesizing a monoalkyl tin triamide compound having formula (1) and containing no detectable amount of a dialkyl tin diamide compound having formula (2):

• wherein R1 and R1′ are each independently a primary alkyl group having about 1 to 10 carbon atoms or a secondary alkyl group having about 3 to 10 carbon atoms, the method comprising:
• (a) lithiating a dialkylamine in a solution containing a first solvent to produce a lithium dimethylamide having a concentration in the solution of up to about 10 wt %;
• (b) adding a solution of tetrakis(dialkylamino)tin in a second solvent to the lithium dimethylamide at about −15° C. to about 0° C. to produce a reaction mixture, wherein an amount of tetrakis(dialkylamino)tin in the reaction mixture is about 0.3 mol % to about 2 mol % relative to the amount of the lithium dialkylamide;
• (c) adding a solution of an alkyl trichlorotin compound R1SnCl3 in a third solvent to the reaction mixture at about −15° C. to about 0° C., wherein the amount of lithium dimethylamide in the reaction mixture is at least about 3.09 equivalents relative to the amount of the alkyl trichlorotin compound;
• (d) removing the LiCl salt product by filtration;
• and
• (e) removing the first solvent, the second solvent, and the third solvent under vacuum to produce a product containing the monoalkyl tin triamide having formula (1) and no detectable amount of the dialkyl tin diamide compound having formula (2).

A method for producing a tin composition (P1) comprising a monoalkyl tin compound having formula (A1) and a purity of at least about 80 mol %, the method comprising contacting a raw material tin compound having formula (B1) and a reactant (M1) in an organic solvent and blending the raw material tin compound having formula (B1) and the reactant (M1) in the organic solvent for a blending time period t at a contact temperature T1, wherein the blending is performed at the contact temperature T1 for at least half of the time period t, and wherein the contact temperature T1 is in a range of about 10° C. to about 70° C., and wherein:

• (a) at least 50% by weight of the raw material tin compound having formula (B1) is blended with the reactant (M1) at the contact temperature T1, or
• (b) at least 50% by weight of the reactant (M1) is blended with the raw material tin compound having formula (B1) at the contact temperature T1:
• wherein R2 is an organic group having about 1 to 30 carbon atoms, which may be substituted with at least one halogen, oxygen, or nitrogen atom, each X2 is independently selected from the group consisting of OR2′, NR2′2, and C≡CR2′, wherein each R2′ is independently an organic group having about 1 to 10 carbon atoms, which may be substituted with at least one halogen, and wherein when there is more than one R2′ in a molecule, they may be the same or different and may be bonded together to form a cyclic structure, each Y2 is independently selected from the group consisting of halogen atoms, OR′, and NR′2, and
• wherein (M1) is a compound having formula MX2, MX22, or MX23, where M represents a metal atom of Group 1, 2, 12, or 13.

A method for producing a tin composition (P1) comprising a monoalkyl tin compound having formula (A1) and a purity of at least about 80 mol %, the method comprising contacting a raw material tin compound having formula (B1) and a reactant (M1) in an organic solvent and blending the raw material tin compound having formula (B1) and the reactant (M1) in the organic solvent for a blending time period t at a contact temperature T1, wherein the blending is performed at the contact temperature T1 for at least half of the time period t, and wherein a lower limit of T1 is a temperature at which a formation ratio (A1)/(A2) of the monoalkyl tin compound having formula (A1) from a reaction intermediate R2SnX22Y2 to the dialkyltin compound having formula (A2) from a disproportionation of R2SnX22Y2 is 600 or more and an upper limit of T1 is less than a lowest value of the decomposition temperatures of (B1), (A1) and (M1), and wherein:

• (a) at least 50% by weight of the raw material tin compound having formula (B1) is blended with the reactant (M1) at the contact temperature T1, or
• (b) at least 50% by weight of the reactant (M1) is blended with the raw material tin compound having formula (B1) at the contact temperature T1:
• wherein R2 is an organic group having about 1 to 30 carbon atoms, which may be substituted with at least one halogen, oxygen, or nitrogen atom, each X2 is independently selected from the group consisting of OR2′, NR2′2, and C≡CR2′, wherein each R2′ is independently an organic group having about 1 to 10 carbon atoms, which may be substituted with at least one halogen, and wherein when there is more than one R2′ in a molecule, they may be the same or different and may be bonded together to form a cyclic structure, each Y2 is independently selected from the group consisting of halogen atoms, OR′, and NR′2, and
• wherein (M1) is a compound having formula MX2, MX22, or MX23, where M represents a metal atom of Group 1, 2, 12, or 13.

A method for producing a tin composition (P11) comprising a monoalkyl tin compound having formula (A11), the method comprising contacting a raw material tin compound having formula (B11) and a reactant (M11) in an organic solvent and blending the raw material tin compound having formula (B11) and the reactant (M11) in the organic solvent for a blending time period t at a contact temperature T1, wherein the blending is performed at the contact temperature T1 for at least half of the time period t, and wherein the contact temperature T1 is in a range of about 10° C. to about 70° C., and wherein:

• (a) at least 50% by weight of the raw material tin compound having formula (B11) is blended with the reactant (M11) at the contact temperature T1, or
• (b) at least 50% by weight of the reactant (M11) is blended with the raw material tin compound having formula (B 11) at the contact temperature T1:
• wherein each R2″″ is independently a secondary or tertiary organic group having about 3 to 30 carbon atoms, which may be substituted with at least one halogen atom, oxygen atom or nitrogen atom;
• each R2′ is independently an organic group having about 1 to 10 carbon atoms, which may be the same or different and may be substituted with at least one halogen atom;
• each R2″ is independently an organic group having about 2 to 10 carbon atoms, which may be the same or different and may be substituted with at least one halogen atom, and wherein when there is more than one R2″ in a molecule, the structures may be different from each other, and may be bonded together to form a cyclic structure;
• and
• wherein (M11) is a compound having formula HOR2″.

A method for producing a tin composition (P1) comprising a monoalkyl tin compound having formula (A1) and a purity of at least about 80 mol %, the method comprising contacting a raw material tin compound having formula (B1) and a reactant (M2) in an organic solvent and blending the raw material tin compound having formula (B1) and the reactant (M2) in the organic solvent for a blending time period t at a contact temperature T1, wherein the blending is performed at the contact temperature T1 for at least half of the time period t, wherein the contact temperature T1 is in a range of about 10° C. to about 70° C., and wherein:

• at least 50% by weight of the raw material tin compound (B1) is blended with the reactant (M2), or the blade tip speed, calculated by the following formula as the agitation speed when at least 50% by weight of the raw material tin compound (B1) is blended with the reactant (M2), is 1.2 m/s or higher;
• blade tip speed (m/s)=3.14×number of revolutions (rpm)×diameter of mixing blade (m)/60:
• wherein R2 is an organic group having about 1 to 30 carbon atoms, which may be substituted with at least one halogen, oxygen, or nitrogen atom, each X2 is independently selected from the group consisting of OR2′, NR2′2, and C≡CR2′, wherein each R2′ is independently an organic group having about 1 to 10 carbon atoms, which may be substituted with at least one halogen, and wherein when there is more than one R2′ in a molecule, they may be the same or different and may be bonded together to form a cyclic structure, each Y2 is independently selected from the group consisting of halogen atoms, OR′, and NR′2, and
• wherein (M2) is a compound having formula MX2, MX22, MX23, or HX2 where M represents a metal atom of Group 1, 2, 12, or 13.

A method for producing a tin composition (P1) comprising a monoalkyl tin compound having formula (A1) and a purity of at least about 80 mol %, the method comprising contacting a raw material tin compound having formula (B1) and a reactant (M2) in an organic solvent and blending the raw material tin compound having formula (B1) and the reactant (M2) in the organic solvent for a blending time period t at a contact temperature T1, wherein the blending is performed at the contact temperature T1 for at least half of the time period t, and wherein the contact temperature T1 is in a range of about 10° C. to about 70° C., and wherein the organic solvent has a moisture content of 10 to 80 ppm:

• wherein R2 is an organic group having about 1 to 30 carbon atoms, which may be substituted with at least one halogen, oxygen or nitrogen atom, each X2 is independently selected from the group consisting of OR2′, NR2′2, and C≡CR2′, wherein each R2′ is independently an organic group having about 1 to 10 carbon atoms, which may be substituted with at least one halogen, and wherein when there is more than one R2′ in a molecule, they may be the same or different and may be bonded together to form a cyclic structure, each Y2 is independently selected from the group consisting of halogen atoms, OR′, and NR′2, and
• wherein (M2) is a compound having formula MX2, MX22, MX23, or HX2 where M represents a metal atom of Group 1, 2, 12, or 13.

A method for producing an organotin compound, comprising steps of:

• mixing a crude product containing an organotin compound having formula (a1) with an additive (b1) to form a mixture (x1) containing the crude product and the additive (b1), and
• recovering the organotin compound (a1) having a purity of 95 mol % or higher by distilling the mixture (x1) containing the crude product and the additive (b1):
• wherein in the formula (a1), R3 represents a hydrocarbon group having about 1 to 30 carbon atoms, which may each be substituted with a halogen atom, an oxygen atom, or a nitrogen atom,
• each X3 is independently OR3′ or NR3′2, wherein R3′ is a hydrocarbon group having about 1 to 30 carbon atoms, which may each be substituted with a halogen atom, an oxygen atom, or a nitrogen atom, the three R3′ may be the same or different from each other;
• and R3 and R3′ may be bonded to each other to form a cyclic structure;
• the additive (b1) is a hydrocarbon compound containing about 2 to about 20 carbon atoms substituted with at least one nitrogen and/or oxygen atom and satisfies a condition (1a) and a condition (2):
• condition (1a):
• when the number of nitrogen atoms in the hydrocarbon compound is m and the number of oxygen atoms is n, m is 0, 1, 2 or 3, n is 0, 1, 2 or 3, and m+n is 2 or 3;
• condition (2):
• in the hydrocarbon compound, when the number of nitrogen atoms among the m nitrogen atoms that are bonded to a hydrogen atom is defined as x, and the number of oxygen atoms among the n oxygen atoms that are bonded to a hydrogen atom is defined as y, x+y is 1 or more.

A method for producing an organotin compound, comprising:

• mixing a crude product containing an organotin compound having formula (a1) with an additive (b2) to form a mixture (x2) containing the crude product and the additive (b2),
• wherein the mixture (x2) further contains an organotin compound having formula (a3), and wherein an amount of the additive (b2) in the mixture is about 0.5 to 10 times an amount of the organotin compound having formula (a3):
• wherein R3 represents a hydrocarbon group having about 1 to 30 carbon atoms, which may each be substituted with a halogen atom, an oxygen atom, or a nitrogen atom, and
• each X3 is independently OR3′ or NR3′2, wherein R3′ is a hydrocarbon group having about 1 to 30 carbon atoms, which may be substituted with a halogen atom, an oxygen atom, or a nitrogen atom, the three R3′ may be the same or different from each other;
• and R3 and R3′ may be bonded to each other to form a cyclic structure;
• the additive (b2) is a hydrocarbon compound containing about 2 to about 20 carbon atoms substituted with at least one nitrogen and/or oxygen atom and satisfies a condition (1b) and a condition (2):
• condition (1b):
• when the number of nitrogen atoms in the hydrocarbon compound is m and the number of oxygen atoms is n, m is 0, 1, 2, 3, 4, or 5, n is 0, 1, 2, 3, 4, or 5, and m+n is 2, 3 4, 5,6, 7, 8, 9, or 10;
• condition (2):
• in the hydrocarbon compound, when the number of nitrogen atoms among the m nitrogen atoms that are bonded to a hydrogen atom is defined as x, and the number of oxygen atoms among the n oxygen atoms that are bonded to a hydrogen atom is defined as y, x+y is 1 or more.

A method for producing an organotin compound, comprising steps of:

• mixing a crude product containing an organotin compound having formula (a1) with an additive (b3) to form a mixture (x3) containing the crude product and the additive (b3), and
• recovering the organotin compound (a1) with a purity of 95 mol % or higher by distilling the mixture (x3) containing the crude product and the additive (b3);
• wherein in the formula (a1), R3 represents a hydrocarbon group having about 1 to 30 carbon atoms, which may be substituted with a halogen atom, an oxygen atom, or a nitrogen atom, and
• each X3 is independently OR3′ or NR3′2, wherein R3′ is a hydrocarbon group having about 1 to 30 carbon atoms, which may be substituted with a halogen atom, an oxygen atom, or a nitrogen atom, the three R3′ may be the same or different from each other;
• and R3 and R3′ may be bonded to each other to form a cyclic structure;
• and
• the additive (b3) is a polymer resin containing sulfur atoms.

A method for producing an organotin compound, comprising steps of:

• mixing a crude product containing an organotin compound having formula (a1) with an additive (b2) and an organic solvent to form a mixture (x4) containing the crude product, the additive (b2), and the organic solvent, and
• recovering the organotin compound (a1) with a purity of 95 mol % or higher by distilling the mixture (x4) containing the crude product, the additive (b2), and the organic solvent, wherein
• a content of the organic solvent in the mixture (x4) is 100 parts by mass or more relative to 100 parts by mass of the additive (b2);
• wherein R3 represents a hydrocarbon group having about 1 to 30 carbon atoms, which may be substituted with a halogen atom, an oxygen atom, or a nitrogen atom, and
• each X3 is independently OR3′ or NR3′2, wherein R3′ is a hydrocarbon group having about 1 to 30 carbon atoms, which may be substituted with a halogen atom, an oxygen atom, or a nitrogen atom, the three R2′ may be the same or different from each other;
• and R3 and R3′ may be bonded to each other to form a cyclic structure;
• the additive (b2) is a hydrocarbon compound containing about 2 to about 20 carbon atoms substituted with at least one nitrogen and/or oxygen atom and satisfies a condition (1b) and a condition (2):
• condition (1b):
• when the number of nitrogen atoms in the hydrocarbon compound is m and the number of oxygen atoms is n, m is 0, 1, 2, 3, 4, or 5, n is 0, 1, 2, 3, 4, or 5, and m+n is 2, 3 4, 5,6, 7, 8, 9, or 10;
• condition (2):
• in the hydrocarbon compound, when the number of nitrogen atoms among the m nitrogen atoms that are bonded to a hydrogen atom is defined as x, and the number of oxygen atoms among the n oxygen atoms that are bonded to a hydrogen atom is defined as y, x+y is 1 or more.

A method for producing a tin composition (P1) comprising a monoalkyl tin compound having formula (A1) and a purity of at least about 95 mol %, the method comprising contacting a raw material tin compound having formula (B1) and a reactant (M1) in an organic solvent and blending the raw material tin compound having formula (B1) and the reactant (M1) in the organic solvent for a blending time period t at a contact temperature T1 to produce a crude product, wherein the blending is performed at the contact temperature T1 for at least half of the time period t, and wherein the contact temperature T1 is in a range of about 10° C. to about 70° C., and wherein:

• (a) at least 50% by weight of the raw material tin compound having formula (B1) is blended with the reactant (M1) at the contact temperature T1, or
• (b) at least 50% by weight of the reactant (M1) is blended with the raw material tin compound having formula (B1) at the contact temperature T1:
• wherein R2 is an organic group having about 1 to 30 carbon atoms, which may be substituted with at least one halogen, oxygen or nitrogen atom, each X2 is independently selected from the group consisting of OR2′, NR2′2, and C≡CR2′, wherein each R2′ is independently an organic group having about 1 to 10 carbon atoms, which may be substituted with at least one halogen, and wherein when there is more than one R2′ in a molecule, they may be the same or different and may be bonded together to form a cyclic structure, each Y2 is independently selected from the group consisting of halogen atoms, OR′, and NR′2, and
• wherein (M1) is a compound having formula MX2, MX22, or MX23, where M represents a metal atom of Group 1, 2, 12, or 13;
• the method further comprising:
• mixing the crude product with an additive (b1) to form a mixture (y1) containing the crude product and the additive (b1), and
• recovering the tin composition (P1) comprising the monoalkyl tin compound having formula (A1) and a purity of at least about 95 mol %, by distilling the mixture (y1) containing the crude product and the additive (b1):
• wherein the additive (b1) is a hydrocarbon compound containing about 2 to about 20 carbon atoms substituted with at least one nitrogen and/or oxygen atom and satisfies a condition (1a) and a condition (2):
• condition (1a):
• when the number of nitrogen atoms in the hydrocarbon compound is m and the number of oxygen atoms is n, m is 0, 1, 2 or 3, n is 0, 1, 2 or 3, and m+n is 2 or 3;
• condition (2):
• in the hydrocarbon compound, when the number of nitrogen atoms among the m nitrogen atoms that are bonded to a hydrogen atom is defined as x, and the number of oxygen atoms among the n oxygen atoms that are bonded to a hydrogen atom is defined as y, x+y is 1 or more.

A method of purifying a mixture containing a monoalkyl tin triamide compound having formula (1), no detectable amount of a dialkyl tin diamide compound having formula (2), and about 0.1 to about 5 mol % of a tetrakis(dialkylamino)tin compound having formula (8):

• wherein R1 and R1′ are each independently a primary alkyl group having about 1 to about 10 carbon atoms or a secondary alkyl group having about 3 to about 10 carbon atoms, the method comprising:
• adding at least one weak acid, at least one weak base, at least one weak acid polymer, or at least one weak base polymer to the mixture containing compounds (1) and (8) at about 15° C. to about 30° C. to produce a reaction mixture, wherein an amount of the at least one weak acid, the at least one weak base, the at least one weak acid polymer, or the at least one weak base polymer in the reaction mixture is at least about 2 equivalents relative to the amount of compound (8);
• and
• removing reaction byproducts to produce a mixture containing the monoalkyl tin triamide having formula (1), no detectable amount of the dialkyl tin diamide compound having formula (2), and no detectable amount of the tetrakis(dimethylamino)tin compound having formula (8).

A method of purifying a mixture containing a monoalkyl tin triamide compound having formula (1), less than 0.05 mol % of a dialkyl tin diamide compound having formula (2), and about 0.1 to about 5 mol % of a tetrakis(dialkylamino)tin compound having formula (8):

• wherein R1 and R1′ are each independently a primary alkyl group having about 1 to about 10 carbon atoms or a secondary alkyl group having about 3 to about 10 carbon atoms, the method comprising:
• (a) adding at least one weak acid, at least one weak base, at least one weak acid polymer, or at least one weak base polymer to the mixture containing compounds (1) and (8) at about 15° C. to about 30° C. to produce a reaction mixture, wherein an amount of the at least one weak acid, the at least one weak base, the at least one weak acid polymer, or the at least one weak base polymer in the reaction mixture is at least about 2 equivalents relative to the amount of compound (8);
• and
• (b) removing reaction byproducts to produce a mixture containing the monoalkyl tin triamide having formula (1), less than 0.05 mol % of the dialkyl tin diamide compound having formula (2), and less than 0.1 mol % of the tetrakis(dimethylamino)tin compound having formula (8).