Esta es la versión de autor del artículo publicado en: This is an author produced version of a paper published in: El acceso a la versión del editor puede requerir la suscripción del recurso Access to the published version may require subscription Mo(CO) 6 from 1.0 equiv (43% conversion, entry 1 in Table 149 1) to 0.5 equiv (67% conversion, entry 2 in 199 This good trans-diastereoselectivity is remarkable, revealing a 200 marked preference for C−H activation of the pro-S methyl 201 group of (+)-3.23e Importantly, the major (−)-trans-9 202 diastereomer could be isolated in 75% yield with no appreciable 203 loss of enantiopurity (97% ee) upon standard chromatography. 204Although the structure of the bimetallic complex of γ-205 cyclopalladation of tert-leucine derivative (+)-1 (complex A) 206 strongly suggested that the NH−SO 2 Py directing group is 207 crucial for this transformation, we were interested in confirming 208 this issue by screening other potentially coordinating N-209 protecting groups. For this purpose, a set of L-valine derivatives 210 (substrates 4−8) were examined in the carbonylation reaction 211 under the optimized conditions, and the results are summarized 212 in Table 2. While L-valine methyl ester hydrochloride 213 decomposed under the reaction conditions (entry 2 in Table 214 2), the NH-Ts derivative 5 and the NH-(2-thienyl)sulfonyl 215 derivative 6 were recovered unaltered without detecting any 216 carbonylation product (entries 3 and 4, respectively, in Table 217 2). The reaction of the (8-quinolyl)sulfonyl and (2-pyridyl)-218 carbonyl derivatives (7 and 8, respectively) led to a complex 219 mixture of products in low conversion (<10%) (entries 5 and 6 220 in Table 2). Interestingly, the lack of reaction efficiency 87 (75) e 5.7:1 (9) 9 7 2 −(4)a Reaction conditions are identical to those given in Table 1 This method was extended to β-amino acid derivatives, as 260 exemplified by the clean cyclocarbonylation of β-amino ester 261 (±)-19, affording the product (±)-20 as a separable 3.8:1 262 mixture of trans/cis diastereoisomers in good overall yield 263 (76%). 264Extension of the Method to Simple Aliphatic Amines. 265 The broad substrate scope displayed by this reaction with α-266 amino acid derivatives prompted us to explore the extension of 267 this method to simple aliphatic amine derivatives. We first 268 tested if compound (−)-21, analogue to tert-leucine derivative 269 1 but lacking the methyl ester moiety, could undergo γ-270 cyclometalation. The stoichiometric reaction of (−)-21 with 271 Pd(OAc) 2 (1.0 equiv) in acetonitrile at 60°C for 3.5 h, cleanly 272 provided, after simple recrystallization, the expected bimetallic 273 complex B in 91% yield (unambiguously determined by singles3 274 crystal X-ray diffraction (XRD) analysis; see Scheme 3), which 275 presents an analogous structure to complex A. This result demonstrated that the ester group at the α-277 position of the previously studied α-amino ester derivatives was 278 not essential for the C−H activation step. Fu...

A practical copper-catalyzed direct nitration of protected anilines, by using one equivalent of nitric acid as the nitrating agent, has been developed. This procedure features mild reaction conditions, wide structural scope (with regard to both N-protecting group and arene substitution), and high functional-group tolerance. Dinitration with two equivalents of nitric acid is also feasible.

A general and practical Cu(I)-Fesulphos-catalyzed Mannich reaction of glycinate Schiff bases with aliphatic imines generated in situ from α-amido sulfones is described. Imines with linear and branched alkyl chains, including substrates bearing functional groups, can be efficiently applied. The resulting syn-configured orthogonally protected β-alkyl-α,β-diamino acid derivatives are produced with excellent levels of diastereo- (typically syn/anti >90 : <10) and enantioselectivity (generally ≥90% ee).

Catalysis Cu‐catalyzed mono‐ (or di‐) nitration of aniline derivatives, with 1 (or 2) equivalents of HNO3, produces H2O as the only stoichiometric byproduct. For more information, see the Communication by N. Rodríguez, R. Gómez Arrayás, J. C. Carretero, and co‐workers on

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