A method for preparing a reaction product of formula R (4-c) SiX c, where the subscript c is 1, 2, 3, or 4, wherein the method comprises steps and, where: step is contacting, at a temperature from 200°C to 1400°C, a first ingredient comprising a silane of formula H a R b SiX (4-a-b), where subscript a is an integer from 0 to 4, subscript b is 0 or 1, a quantity (a + b) ≤ 4, each R is independently a monovalent organic group, and each X is independently a halogen atom; with a spinel catalyst comprising copper; thereby forming a reactant, with the proviso that when the quantity (a + b) < 4, then the first ingredient further comprises H 2; and step is contacting the reactant with a second ingredient comprising an organohalide at a temperature from 100°C to 600°C; thereby forming the reaction product and a spent reactant; and where the method optionally further comprises steps and, and where step is contacting, at a temperature from 200°C to 1400°C, the spent reactant with an additional first ingredient comprising additional silane of formula H a R b SiX (4-a-b), where subscript a is an integer from 0 to 4, subscript b is 0 or 1, the quantity (a + b) ≤ 4, each R is independently a monovalent organic group, and each X is independently a halogen atom, with the proviso that when the quantity (a + b) < 4, then the additional ingredient further comprises H 2; thereby re-forming the reactant, and step is contacting the reactant re-formed in step with an additional second ingredient comprising organohalide at a temperature from 100°C to 600°C; thereby forming an additional reaction product and an additional spent reactant, and where the method optionally further comprises step, where step is repeating steps and at least one time; and where the method optionally further comprises step after any one or more of steps to, where step is recovering the reaction product, and further comprising: purging and/or treating the spinel catalyst, before contacting the spinel catalyst with the ingredient comprising the silane in step; and/or purging and/or treating the reactant, before contacting the reactant with the organohalide in step; and/or purging and/or treating, the spent reactant before contacting the spent reactant with the additional ingredient in step; and/or purging and/or treating the reactant re-formed in step, before the contacting the reactant re-formed in step with the (additional) organohalide in step; and/or purging and/or treating the additional spent reactant. step is contacting, at a temperature from 200°C to 1400°C, a first ingredient comprising a silane of formula H a R b SiX (4-a-b), where subscript a is an integer from 0 to 4, subscript b is 0 or 1, a quantity (a + b) ≤ 4, each R is independently a monovalent organic group, and each X is independently a halogen atom; with a spinel catalyst comprising copper; thereby forming a reactant, with the proviso that when the quantity (a + b) < 4, then the first ingredient further comprises H 2; and step is contacting the reactant with a second ingredient comprising an organohalide at a temperature from 100°C to 600°C; thereby forming the reaction product and a spent reactant; and where the method optionally further comprises steps and, and where step is contacting, at a temperature from 200°C to 1400°C, the spent reactant with an additional first ingredient comprising additional silane of formula H a R b SiX (4-a-b), where subscript a is an integer from 0 to 4, subscript b is 0 or 1, the quantity (a + b) ≤ 4, each R is independently a monovalent organic group, and each X is independently a halogen atom, with the proviso that when the quantity (a + b) < 4, then the additional ingredient further comprises H 2; thereby re-forming the reactant, and step is contacting the reactant re-formed in step with an additional second ingredient comprising organohalide at a temperature from 100°C to 600°C; thereby forming an additional reaction product and an additional spent reactant, and purging and/or treating the spinel catalyst, before contacting the spinel catalyst with the ingredient comprising the silane in step; and/or purging and/or treating the reactant, before contacting the reactant with the organohalide in step; and/or purging and/or treating, the spent reactant before contacting the spent reactant with the additional ingredient in step; and/or purging and/or treating the reactant re-formed in step, before the contacting the reactant re-formed in step with the (additional) organohalide in step; and/or purging and/or treating the additional spent reactant.