NaH, like LiH, KH, RbH, and CsH, adopts the NaCl crystal structure. Attacks SiO2 in glass. Product name : Sodium Hydride CAS-No. Properties of Sodium hydride NaH: White. 2NaH + 4C (graphite) = Na2C2 + C2H2 (350°C). Si-Si and S-S bonds in disilanes and disulfides are also reduced. 4 The bulky tert-butyl group will not hinder the hydride attacking from the top face. Decomposes when heated, under hydrogen pressure melts without decomposition. Both sodium borohydride and lithium aluminum hydride are smaller, less bulky metal hydride reducing agents, and thus it is expected that they will be able to deliver the hydride from the top face of the molecule (see “Figure 1” and “Figure 2”). Two practical sources of hydride-like reactivity are the complex metal hydrides lithium aluminum hydride (LiAlH 4) and sodium borohydride (NaBH 4). SODIUM HYDRIDE NaH. Health effects/safety hazards: The main hazards from sodium hydride are its flammability and violent, explosive reaction with air and water. Moreover, it also forms the highly flammable hydrogen gas and strong base, NaOH, which can lead to further danger. This is followed by Step 6 where sodium hydride reacts with trimethylborate to make sodium borohydride and sodium methoxide. Sodium borohydride, a representative borohydride reagent, behaves as an effective source of nucleophilic hydride in an aprotic polar solvent, such as DMSO, sulfolane, HMPA, DMF or diglyme, and is used for the reduction of alkyl halides.93,94 As shown in Table 3, primary and secondary iodides, bromides and chlorides are converted to hydrocarbons at temperatures between 25 and 100 °C using sodium borohydride. Sodium hydride (NaH) reacts with water (H2O) and produce sodium hydroxide (NaOH) and hydrogen gas. This reaction likely occurs through a disproportionation, wherein the simple acid-base adduct sodium trimethoxyborohydride NaH is a base of wide scope and utility in organic chemistry. It is an ionic material that is insoluble in organic solvents (although soluble in molten Na), consistent with the fact that H ions do not exist in solution. 2Na2[ReH9] = 4 NaH + 2 Re + 7H2 (245°C). Sodium hydride is the chemical compound with the empirical formula NaH. Sodium hydride is a severe irritant to skin and eyes. Work up guide Work-up is a procedure to obtain crude product from a reaction. A traditional $\ce{S_{N}2}$ reaction takes place. One challenge with this technology is the regeneration of NaH from the NaOH.[14]. Although the reaction of carbonyl compounds with sodium hydride is heterogeneous and slow, sodium enolates are formed with the loss of hydrogen, and no other organic compounds are produced. Sodium hydride (NaH), when used with certain solvents, can unexpectedly generate heat and gas, leading to a runaway reaction or even an explosion (Org. The ionic radii of H− (146 pm in NaH) and F− (133 pm) are comparable, as judged by the Na−H and Na−F distances. The second reaction shows the isotopic exchange that occurs when mixing an alcohol with deuterium oxide (heavy water). [7] Pure NaH is colorless, although samples generally appear grey. SODIUM HYDRIDE is a powerful reducing agent. Steam Reforming of Methane to Make Hydrogen 2. NaH is used to make sulfur ylides, which in turn are used to convert ketones into epoxides, as in the Johnson–Corey–Chaykovsky reaction. In case of contact with eyes, they should be rinsed with large amounts of water, under the eyelids for at least 15 minutes and seek medical attention immediately. This is an ionic compound that is composed of the sodium cation and hydride anion. SODIUM HYDRIDE is a powerful reducing agent. NaH is widely used to promote condensation reactions of carbonyl compounds via the Dieckmann condensation, Stobbe condensation, Darzens condensation, and Claisen condensation. Draw the curved arrow notation to form the intermediate. Ignites on contact with gaseous F2, Cl2, Br2, and I2 (the last at temperatures exceeding 100°C), especially in the presence of moisture, to form HF, HCl, HBr, and HI [Mellor 2:483 1946-47]. Reactions involving NaH require air-free techniques. 2Na + H2 = 2 NaH (250-400°C, pressure). Nevertheless, an alcohol, often methanol or ethanol, is generally the solvent of choice for sodium borohydride reductions of ketones and aldehydes. 2Na2[ReH9] = 4 NaH + 2 Re + 7H2 (245°C). Process Res. Actually i am trying to abstract N-H proton of an amide using sodium hydride as a base. 2NaH + 2 SO2 = Na2SO4 + H2S (200-250°C). All reactions should be done under an inert atmosphere. To complement the answer provided by @Ian Fang and edited by @santiago, sodium hydride's action as a Brønsted base differs from other bases. NaBH 4 reacts with water and alcohols, with evolution of hydrogen gas and formation of the corresponding borate, the reaction being especially fast at low pH. Sodium hydride is sold as a mixture of 60% sodium hydride (w/w) in mineral oil. 2NaH + (FeIIFe2III)O4 = 4NaOH + 3Fe (350-420°C). The resulting sodium derivatives can be alkylated. Sodi­um hy­drox­ide is a sub­stance that is clas­si­fied as an al­ka­li. When does Product 452912, Sodium hydride in Mineral Oil, decompose? According to literature, this product starts to decompose with the evolution of hydrogen at about 255 deg C and completely decomposes at 800 deg C ( Condensed Chemical Dictionary, Twelfth Edition ). [15], Except where otherwise noted, data are given for materials in their, Index no. The most common sources of the hydride nucleophile are lithium aluminium hydride (LiAlH 4) and sodium borohydride (NaBH 4 ). Sodium hydride (NaH), when used with certain solvents, can unexpectedly generate heat and gas, leading to a runaway reaction or even an explosion (Org. Hydrofluoric acid is so corrosive that it will dissolve glass. Sodium hydride is considered corrosive to the skin or eyes due to the caustic byproducts of water reactions. Typically NaH is used as a suspension in THF, a solvent that resists attack by strong bases but can solvate many reactive sodium compounds. 40% denser than Na (0.968 g/cm3). NaH is a saline (salt-like) hydride, composed of Na and H ions, in contrast to molecular hydrides such as borane, methane, ammonia and water. All reactions should be done under an inert atmosphere. Contact with sodium hydride by itself can burn eyes and skin. [12] Notably boron trifluoride reacts to give diborane and sodium fluoride:[7]. Sodium Hydride is an inorganic compound and a strong base too. In this motif, each Na+ ion is surrounded by six H− centers in an octahedral geometry. alkali/alkaline earth metal hydrides such as sodium hydride (NaH) are also readily available chemicals, which are utilized almost exclusively as a strong Brønsted base for routine depro-tonation reactions in chemical synthesis (2,3 The Scheme 1B). It is primarily used as a strong base in organic synthesis.NaH is representative of the saline hydrides, meaning it is a salt-like hydride, composed of Na + and H − ions, in contrast to the more molecular hydrides such as borane, methane, ammonia and water. This molecule irreversibly encapsulates the H+ and shields it from interaction with the alkalide Na−. SODIUM HYDRIDE NaH. 4NaH + AlCl3= Na[AlH4] + 3NaCl (in ether). This alkali metal hydride is primarily used as a strong yet combustible base in organic synthesis. When taking into account the steps of raw materials production, the overall NaBH4 process consists of seven steps: 1. Dev. Sodium hydride (NaH) reacts violently with water, liberating hydrogen gas . Let stand until solids settle. NaH reduces certain main group compounds, but analogous reactivity is very rare in organic chemistry (see below). It is an ionic material that is insoluble in organic … 1.3 Details of the supplier of the safety data sheet Company : Central Drug House (P) Ltd 7/28 Vardaan House New Delhi-10002 INDIA Due to the insolubility of sodium hydride in all solvents and high reactivity with atmospheric moisture, solutions dealing with the associated … A strong reducing agent, reacts with water, acids, ammonia and oxygen. NaH notably deprotonates carbon acids (i.e., C-H bonds) such as 1,3-dicarbonyls such as malonic esters. Ignites on contact with gaseous F2, Cl2, Br2, and I2 (the last at temperatures exceeding 100°C), especially in the presence of moisture, to form HF, HCl, HBr, and HI [Mellor 2:483 1946-47]. Attacks SiO2 in glass. Due to the insoly. Obtaining Sodium hydride: 2Na + H2 = 2 NaH (250-400°C, pressure). Due to the insolubility of sodium hydride in all solvents and high reactivity with atmospheric moisture, solutions dealing with the associated safety concerns on kilogram scale are described. Vicinal dihalides, such as 1,2-dibromooctane, are smoothly co… The first reaction shows simple alcohols with sodium (and sodium hydride). The coupling reaction with sodium hydride has been used for the synthesis of ligands chiral at phosphorus, such as Ph2(S)PNHP*(S)Ph(OPh) and (PhO)2(Q1)PNHP*(S)Ph(OPh) (Q1 = O or S).47These compounds are combined from phosphinyl (or phosphoryl) with phosphonyl fragments and are the only representatives of this type reported. Sodium hydride was found to be the best base for a displacement reaction on a chloropyrimidine. of sodium hydride in all solvents and high reactivity with atm. The following is general guidelines to quench a reaction. The first reaction shows simple alcohols with sodium (and sodium hydride). Actually i am trying to abstract N-H proton of an amide using sodium hydride as a base. Sodium hydride was found to be the best base for a displacement reaction on a chloropyrimidine. Sodium hydride is a severe irritant to skin and eyes. [8], A very unusual situation occurs in a compound dubbed "inverse sodium hydride", which contains Na− and H+ ions. [9] Theoretical work has suggested that even an unprotected protonated tertiary amine complexed with the sodium alkalide might be metastable under certain solvent conditions, though the barrier to reaction would be small and finding a suitable solvent might be difficult.[10]. Decomposes when heated, under hydrogen pressure melts without decomposition. Reactions with Sodium hydride: What is Sodium Hydride? The compound is often used in this form but the pure grey solid can be prepared by rinsing the commercial product with pentane or THF, with care being taken because the waste solvent will contain traces of NaH and can ignite in air. NaH is produced by the direct reaction of hydrogen and liquid sodium. A broad range of aliphatic ester substrates were reduced to primary alcohols by Na-D15/i-PrOH with good yields. Both sodium borohydride and lithium aluminum hydride are smaller, less bulky metal hydride reducing agents, and thus it is expected that they will be able to deliver the hydride from the top face of the molecule (see “Figure 1” and “Figure 2”).